Archive 7/16

1,479 thoughts on “Archive 7/16

  1. I accidentally washed out Aramith pool balls in detergent and it left a white marble stain on them. What can I do to fix them?

  2. Hi. i`m worried as i used bleach spray on my kitchen tiled floor and to clean it up i used some wipe containing ispropyl alcohol.

  3. Hello everyone out there Am Mrs Linda Edward from Miami Florida US. this is a true life story about how my husband was diagnosed with prostate cancer on July 18, 2016. and got cured by Rick via email that we got the oil from

    If not for the mis-understanding and skeptism my mom would not have died of her lung cancer today. We never knew that cannabis oil can cure cancer, if not my lovely and adorable mom wouldn\’t have die of her lung cancer, well all the same i still gat to give God all the glory and a big thanks to Dr Rick who provided me with CANNABIS oil for my husband liver cancer cure, after i lost my mum to lung cancer 2 years later my husband was diagnosed with prostate cancer he under-go many chemo\’s and radiation treatment in seeking solution to cure the prostate cancer we spent all we gat but all to no avail until I mean\’t a friend of mine who directed me to Rick Simpson Cannabis Oil via Email:

    I quickly emailed him and in less than hour, i got a feed back from him and he directed me on how to purchase the medication cannabis oil and he told me the delivery logistics which i quickly responded to,after two days of procuring the oil, the oil was deliver to me as he promise me. immediately my husband commenced with treatment with the cannabis oil as directed by the prescription manual.

    To God be the glory after using the oil for couple of months (Three months) my husband is free from cancer and today me and my husband are living happily but it is a sad story that my mum didn\’t have this opportunity to survive it, once again you have to be aware that there is cure for cancer diseases today contact Rick via his email, save a life today!!!!


  4. I have bathroom floor tiles and the grout ( quite thick grout ) is a grey but it is dirty and I need to get it back to clean any ideas ?

    • Get some washing soda and use it as a powder cleaner. Wet a small brush, dip it in the washing soda and scrub the grout and it’ll come clean immediately

  5. Hi
    I used oven pride to clean my oven and some went on the outer part of the door.It is a black oven and now the colour has changed its got marks on it from the oven pride solution that dripped onto it.What can I use to get it it back to normal looking ?

  6. Hi Dr Chemnical could you please advise the best way to clean paint from colourbond
    roofs ,gutters
    Many thanks regards Greg

    • Very difficult – colorbond is a lot more strongly bound than ordinary paint, but if anything will work it’s Citristrip from Masters. But I don’t think it will.

    • Tried your 1cup hydrochloric acid / 1cup pool salt / 5lts water spray to kill my plethora of weeds. 3 days now and no sign of death !!! Is there a Sure Fire solution ?

      • Yep. More acid and more salt. You want at least a 20% solution of acid. Alternatively, some lightly applied diesel will do it

  7. Hi Dr Chemical (soon to be parlitarian);
    Hope to the election goes well for you, thanks for standing up for farmers, I am one!

    What gets scuff marks (from shoes i presume) off wooden floors. I have tried ammonia, almost 50:50 with water, but find im scubbing really hard still.


    • Try oven cleaner. Use one that produces a fine spray. Spray on, wait 5 min then wipe off. Or if that doesn’t work, Citristrip Gel from Masters. Or soak a rag with metho, and leave it one the marks for a couple of hours – that should loosen it up

  8. Hi Dr Chemical.
    i have dark grey bathroom floor tiles and also in the shower recess. there are white stains on the tiles, which i expect is very old staining from chemicals in the water. I live in Perth, WA. Do you know of a product which will shift these stubborn stains?

        • Use cerapol, from Bunnings and probably Coles. (Still need elbow grease and a fine steel wool, but it works.) It took many trials with all sorts of products to find a working solution that removes Perth water stains off shower glass!!

  9. Hi… I have an above ground empty pool with bad stains (which don’t react to chlorine) and I was wondering if I could try putting some acetone on a cloth and rubbing it to see what happens? I don’t want to harm the vinyl liner and it just doesn’t seem to scrub off.

    • It’s unlikely to be organic, so acetone probably wouldn’t work. Not sure what it would be without more details, but try Oven Cleaner or Brasso

  10. I have recently bought a beautiful navy blue Lofra cooker.
    It is truly my pride and joy we are so very happy with it..
    I have been trying very hard to remove the blue tape because I never saw it on the sides of the door and I cooked with it twice so it was so difficult but eventually some “meths” took it off beautifully but I never realised what would happen to the navy part of the stove if touched by meths… i feel like the biggest idiot.
    Please please tell me that you have some sort of solution to my problem… How can I remove the lighted area affected by the “meths”
    Thank you

    • Meths is very unlikely to have damaged anything. The difference in colour is probably just that bit is cleaner. With time it’ll probably blend in.

  11. Hi Dr Chemical, I put foil just using water to stick on my windows to block out harsh sunlight in my apartment. Now I’ve taken them off and there’s a residue left that I cannot get off!! Tried razors, jif, vinegar, WD40, alcohol!! What will dissolve this as elbow grease aint doin it!

    • Hydrochloric acid. It’s got a nasty smell but it’s harmless. If that doesn’t do it nothing will. Wear some gloves, put some on a rag and rub on. Try to avoid breathing the fumes, but if you do, don’t worry too much. It’s an irritant but is not toxic.

  12. Good evening. I would likr to know how to clean my ceiling fans. Stainless steel in kitchen. White metal in bedrooms. And have outdoor stainless steel outside.
    I have used enjo cloth. Its a lot of elbow work and still has a sticky resisdue following cleaning. Thanks.

  13. G’day Dr Chemical,
    I’m back again with the shirt vs Expanda Foam problem.
    First day I used a rag and my thumb nail, second day rag and finger nail brush but I still have the nasty whitish stain remaining.
    Do you have any further suggestions please?

    • You tried the acetone? It needs to be soaked for at lease a minute or so. If that doesn’t work a steam cleaner (with a jet nozzle) might work as thw whiet foam is physically but not chemically bound to the shirt.

      • Yeh drowned it in acetone–I’ve use nearly 400ml, also tried metho (hic) and Bam.
        It’s certainly bound to the shirt.
        Havta think about how to steam clean it.

        Thanks very much for your help.


  14. Dr I’ve got Japanese knot weed in my garden – had it now for four years. Gradually going but could I use diluted sulfuric acid to get rid of the last bits as I’m having my garden done next week and its still there?

  15. G’day Dr Chemical,

    I’ve managed to get some Bostik Expanda Foam on to a relatively new blue/grey polyester/cotton Yakka work shirt (Yeh I know–careless silly old &%$$#@)

    I’ve scraped the bulk off but I’m left with a whitish stain.
    Do you have a removal solution please?



    • Acetone should get it out. Metho might work if you have some lying around but not as well as the acetone

  16. Also, is there a way for you to upgrade the question page so it’s not just one single conversation? Hard to get to the end on a mobile device!

    • Yes that’s one of the things that I want to get onto. This site was set up without thought to mobile devices. I’ll be getting a major site upgrade later in the year

    • Potentially. Many components of laundry detergents are alkaline, so a bit of acid wouldn’t hurt. On the other hand, laundry detergents are formulated to wash out readily, so I couldn’t see that this would be a problem unless you were using a very cheap and nasty detergent and washing in cold water

  17. How do you get very stubborn smoke stains of an enamel Weber Q BBQ lid? I’ve tried the Weber cleaner but it doesn’t get it all off – probably my fault because I let it build up for too long. Is there anything else I could try?

    • Hit it with an oven cleaner (Easy Off is my favourite as it sprays a fine mist). Spray it on, wait ten minutes then wipe off. If that doesn’t shift it, nothing will

  18. Having laid ‘sandy’ coloured porcelain tiles on my Balcony several years ago, several times have got a greyish stain on them. I have tried various cleaning agents without success. Several sites also recommended ‘White Vinegar’ and ‘Bleach’ again without success. Any suggestions??

    • You need something caustic. Spray an oven cleaner on, wait ten minutes then scrub with a stiff broom. Then just hose off

  19. I have a number of high-end vintage Hi Fi items that I’ve come by that seem to have been stained by (I think) tobacco smoke over years of use. The area in question is the brushed silver metal surfaces that were popular back in the 70s. I have no problem with disassembling the equipment if needed to clean these panels. My concern is that these panels have silk-screened lettering which I fear could be dissolved or damaged by ‘typical’ cleaners. Can you recommend or course of action to rid the yellowish staining?

        • Yes and the packaging looks 50y old too. It’s what I call an “evergreen” products – something that sells well despite the absence of any advertising, simply because it works so well

  20. I have a fine woollen jumper that has discoloured. It used to be white but is now a grey colour. I have tried all sorts of cleaners but nothing will bring it back to white. Can you suggest anything to revive my jumper?

    • Enzymes will do it. Get some Biozet Attack and give it a warm wash on the appropriate delicate setting. Temperature is critical. Enzymes are at their most active at 40 degrees, and performance drops away quickly after that when it is warner or cooler. Get yourself a Infra Red thermometer on EBay or from an electronics shop (they’re cheaper on EBay) and adjust your thermostat settings accordingly. A presoak at the right temperature would help too.

  21. Hi, I was trying to make cement bowl into glass bowl but it looks like it is now badly stuck to glass bowl and cement mold is not coming out. Any clue how to take it out without shattering the glass bowl?

  22. dr chemical.
    i like making things with oogoo (silicone and cornstarch) but i have a problem with its smell.
    and the smell never goes away no matter how long u leave it in a ventilated area ,
    is there anything i can do or add to the mixture to make this go away or cover it up or so?

    also, is it safe if a kid puts an oogoo toy in his mouth or so?

    • It won’t hurt your child if he puts it in his mouth. What is the smell? In general terms one of the best all-purpose deodorisers around is bicarb soda. Try using it instead of the cornstarch and see how it goes

  23. Good evening ,

    just wondering how to remove white stains from Pavers . My mother in law has removed old pot plants from her pavers under her alfresco and there is white stains . Looks like Calcium. I tried Hydrocholic Acid but didnt make a difference . Is there any product you can suggest .

    • Try some ammonia. Scrub with a stiff broom or brush and hose. What you really want is a high pressure cleaner though…

  24. I have a mixture of hot pork fat and soy sauce spattered on a 100% polyester with an acrylic coating blind.


  25. Hello

    My husband put on new work boots only to find the the corrugated soles had melted. I am not sure whether the soles are rubber or polyurethane but we now have black footsteps on our purple carpet. The carpet is an 80/20 mix. Are you able to help with this as I realise that I will probably only have one go at getting it right.


    • Go to masters and get some Citristrip gel. Get a small paintbrush and carefully paint it directly onto the marks. Wait half an hour and the try wiping it up with a rag. Try it on a small area first. If that doesn’t work, there is no substiyute for a steam cleaning carpet contractor. If they don’t turn up with a van or truck with a big machine in it, and metres of long silver tubing, don’t waste your money. These are the only steam cleaners that work

    • Use an enzyme cleaner. Biozet Attack liquid will do it. Use it as a spot cleaner. Rub it in with your fingers then rinse. Rpt if necesssary

  26. Somebody lost all their teeth, very suddenly.
    They had been using Roundup and Exitmould on that day. Is it possible that the combination can cause such a thing?

  27. Dear Dr Chemical, I have an automatic Cat waste cleaner from the USA that requires a sanitary solution to work and the product and its supplies are no longer available in Australia.

    I am looking to make my own cleaning solution but need to make sure its safe for plastics and cats

    The original packaging suggests it contains synthetic detergent, quatemary ammonium, and a blend of natural and synthetic perfume oils.

    Is there a commercially (globally) available product that fits this description or is it possible to mix something myself?

    Appreciate your guidance



    • These days all detergents are synthetic, so any dishwashing detg will do, and QACs are the active ingredients in bathroom disinfectant (Like Pine-O-Cleen). Look on the packaging and it will say something like “contains 2% QAC”

  28. Hi there, my son tipped a jar of unconstituted powder paint (waterbased) onto my linen & cotton quilt cover. I vacuumed the loose powder up and can still see a patch of powder colour, which I know will turn into bright green paint colour, when it comes into contact with water. Any suggestions?

    • Well, if adding water will turn it into paint it should be possible to rinse it out before it dries. So I’d hang it on the clothesline, set your hose to “shower” (or some other low pressure setting) and just rinse it with lots and lots of water. With a bit of luck it’ll just rinse out

  29. Dear Dr Chemical. So pleased to find this website. All my light colored tops get a yellow stain around the neck and down the placket. It’s not the usual collar grime as it is also on the area below the collar. Have tried the usual stain remover sprays, soaking in Preen, applying a paste with Preen (in the pink container) and Aldi soaker and left them to dry in the sun. The fabrics are mostly cotton. I don’t use sun screen in that area, nor body moisturizers etc. so that can’t be the cause. I can only think it is some chemical reaction from my body. The stain is so bad that I intend only buy dark colors in future. I do hope you can help me with this as none of my friends seem to have the problem. Thank you. …Margaret

    • I’d have a crack at that with Enzymes. Get some Biozet Attack and use it as a spot cleaner. Tip onto the stain, rub it in with your fingers, then rinse and repeat. The point is that enzymes are temperature dependent, and the optimum temperature is body temperature, so when you rub it in with your fingers, it is the optimum temp. If that doesn’t shift it, then the only options you have are to try an acid (any hard surface cleaner that lists an acid as an ingredient) and a base (any oven cleaner). If none of those shift it then nothing will

  30. Help!
    will muriatic acid or hcl under 10% solution kill my raspberry plants, no buds showing . yet. I need the weeds gone, which have quite a few years hold . i have tried vegetable oil and soap , seems to work but only temporary and same goes for vinegar and soap
    I have pulled a billion weeds, burned them but killed some plants in the process.
    Spraying after leaves start is impossible , so i need to do this asap.

    • Once the acid gets into the soil it’s neutralised pretty quickly, so 10% is probably OK, but I’d throw some salt in there as well.

  31. Hi, I have a few cats and they persist in peeing on my polished wood floor and on a wooden dresser. How can I remove the smell and prevent them going back to the same area ?

    • Use vinegar. It will neutralise the urine smell and should mask the identifying aroma that they use to decide where to pee.

    • The only way to do it is lots of air. Wherever possible park the car with all doors open – there’s no other way to do it. Eventually it will go

  32. Hi Dr Chemical ,
    We own a ski lodge in Japan, that has 2 large Onsen style baths , that fit about 4-5 people in each . We currently use chlorine tablets to keep the water fresh and clear (the baths are used for soaking only , all body washing is done in the adjacent showers) , but the chlorine is quite harsh and I was wondering if we could use any other product to keep the water clear ?

  33. Thanks Dr for helping me with Shampoo and carpet stain issue.

    I have one another issue, we have ceramic tiles in our house, in kitchen area, specially around the dishwasher I see many water spots/stains, I do mop but by the time I mop stains get in the tiles, how do I get rid of these watermarks.


  34. I have water marks on my tiles, especially in kitchen, it’s like when I empty the dishwasher and am arranging, some droplets fall on tiles n I mo after few minutes, tha has left marks/stains, how can I get rid of them.

    Also thanks for helping me with shampoo, I have tried a lot but can’t find pert any where here in perth, do you know where can I get it from?


    • Pert was the first 2 in 1 shampoo on the market – there are probably lots of others now. Look on the instructions and it will normally tell you whether a conditioner is required. Also, you can use Dove (or equivalent). It won’t be as sophisticated as a 2 in 1 shampoo, but it’s the right pH (5.5) for your hair. As a matter of fact you can use any hand soap or body wash that is pH controlled . Look for the phrase “pH controlled” on the back. Or pH 5.5. The reason that conditioners are required for traditional shampoos is that they have a high pH. The conditioner restores the pH to the right level

  35. Good Morning,
    I have white spots all over my brick paving driveway caused by spraying weed killer how can I remove them please?

    • Brick is completely impervious to chemical attack, so all you do is wet the bricks, scrub with a stiff broom and then hose off. Alternatively, go to Bunnings and buy their 3200PSI high pressure Ryobi water cleaning fot about $700. It’s a good investment

  36. Dr Chemical I need your help with two issues today, please help me with it.
    1. Have tried a few shampoo n conditioner but nothing seems to work, alwaysam left is with dry n frizzy hair, can you recommend drugstore shampoo conditioner . I live in Perth , is the hard water also contributing factor?
    2. The other day my husband was working with carpet cleaner solution, may be some got in his slippers , he wasn’t aware, then when he walked with same slipper, it has left very stubborn stains on our tiles. CanI get rid of it.?

    • Can’t help with the shampoo other than to suggest Pert – it’s a 2 in 1 product with a more sophisticated formula than the old shampoo/conditioner formulations. 1 part ammonia in 20 parts water will clean the carpet cleaner off the tiles.

  37. Please can you help? I have just used a spray chandelier cleaner on my chandelier and it has worked well. I have used the same brand before and usually drag my french polished mahogany table underneath the chandelier, cover it well with towels to catch the drips and let the spray do its work. I know it was pretty stupid to use that table but I have never had any problems before. Unfortunately, this time some of the liquid got onto the wood and has left 4 large round areas where it has taken the surface polish off. Is there anything that I can do to repair it? I would be so grateful for some advice. Many thnks, Sonia

    • What brand is the chandelier cleaner? It depends what the active ingredients were, and this determines whether it has removed the polish or has left a residue on top. But in the absence of this information, I’d just try Mr Sheen and see how it goes

  38. Hi Dr Chemical,

    I’ve painted a laminate kitchen surface with a water based wall paint and I need to remove the paint to get back to the original laminate.

    What is the best way to do this without damaging the laminate?

    Thanks Keith

  39. I am having trouble cleaning glass pool fencing. Online instructions say to use warm soapy water but this doesn’t remove the white staining across the glass. Is there something that will dissolve the stain without harming the glass?

  40. Hi there Doc,

    Thanks for your good advice, it has really helped alot.

    I think my sewerage lines are blocked as the toilets in the house not flushing well. What chemical/enzyme can I use to try unblock it, before calling in an expensive plumber.

    Thanks for your advice

    • Caustic Soda solid (pellets or flakes) will do it. Tip a generous amount down the bowl, (a few cupfuls), leave it for 10 minutes and then flush

      • Thanks for that. Tree roots were the cause of the blockage in the main sewer line; I will use your tip with caustic soda for a more localised blockage. Cheers

        P.S I am following your remarks on biodegradability – interesting

  41. Hi, thanks for your time.

    I have installed some new aluminum windows in my house. The aluminium is powder coated and comes with a protective plastic film. I thought I would leave the film on until the building was finished, but the sun has degraded it badly, and it’s impossible to peel off without it breaking up badly.

    I’m after something to assist in removal without affecting the powdercoating or staining the brick that’s next to it, or dissolving the sealant that holds the glass in. I have many, many windows that need to be done.

    Thanks heaps for any help.

    • In order of increasing aggressiveness, turps, xylene (paint thinners), and acetone. But turps should do it,and it won’t damage the sealant or bricks

  42. Hi,

    I have a question regarding using Mr Sheen as a car polish. I’m keen to give it a try but I’ve read elsewhere that the silicon bonds permanently to the paint and is impossible to remove if ever needed (i.e fixing a scratch or dent where paint needs to be re-applied).

    Is there any truth to this or is it just a myth?

    • It’s a myth. It adsorbs strongly but doesn’t bind chemically. Spray painters get it off with Shellite, available from a hardware store

  43. What is the best treatment for chocolate stains from solid/coating chocolate? I get good results with making a paste with a sodium percarbonate product and leaving it for a few hours, have you got a quicker method? Thanks Dr.

    • Yes that’ll work – this is oxidation – the percarbonate is an oxidiser. The only other thing I’d suggest is an enzyme cleaner. Either White King StainLift prewash, or Biozet Attack laundry liquid. Use as a spot cleaner. Rub into stain and then rinse

  44. I accidentally marked three little marks with a red Sharpie fine point permanent marker on my son’s light grey and white cotten drapes. Please give me some hope that I will be able to get this out. Thanking you in advance. ????????

    • Leather is notoriously easy to stain, but if anything will fix it, an enzyme cleaner will (like White King Stain Lift). Problem is though that any water based product will leave a mark, even when the egg is removed. Personally I’d just use good old fashioned shoe polish (Kiwi or Nugget). Rub it in with the shoe polish brush and I reckon that’ll get the mark out

  45. Hi Doctor Chemical!
    I’ve heard a lot about Himalayan Salt being better because table salt has “synthetic iodine” which makes me think it’s garbage as you can’t synthesize a chemical element but I thought you could shed some light in case they add a synthetic compound that contains the iodine maybe?

    Google wasn’t very helpful
    thanks Doc! :)

    • Yes I think you’re right. Iodine is iodine. It sounds to me like the people that sell the Himalayan stuff are trying to get a marketing edge by buying into the “natural is better” myth.

  46. Dear Dr Chemical…I have just discovered your site. I am going to come back for a good read later but right now I’m panicking a bit! I have just moved in to a new rental property. The kitchen has a dark laminate bench top…probably just a layer of laminate on top of something else. I was showing a friend some marks on it and before I could stop her…As I was saying…”Don’t use that!”…she grabbed a Scotch Brite foam scourer and attacked one of the marks!!! There is now a 3cm x3cm area of fine white scratch marks on the bench surface! Can I do anything to restore the pristine glossy finish? (Sound of sobbing :) )
    Sincerely hoping you have a solution?!

    • I’m afraid I can’t help with that one. If anything’ll improve it, it’s Brasso. It’s a fine abrasive that might make the scratch marks less obvious, but it’s never going to restore the original

  47. Hello Dr Chemical
    Is there any way to remove or reduce the smell of latex pillows. I’ve tried the obvious things (like airing, covering with bi-carb. soda and washing) with no result. Are you able to help?

    • The only solution is more air. The smell is caused by the volatile components of the latex, and with enough exposure to air, they will all volatilise (evaporate) off

  48. Hi Dr Chemical I did something really stupid and I need help to eradicate the problem. I was at my wits end when it came to bugs. I recently did some extensions on the house and was just doing some last minute touch ups like liquid gap filler for under the skirting boards and I noticed ants were coming out from one of the gaps. So I went into my dads shed and got his pesticide from out the cupboard and poared it straight onto the concrete inside the room. I then was over whelmed with this putrid smell. So I decided to read the label and oops wasthe first thing that came into my head. It was in an old brown chemical bottle its called BAYTEX Fly and Mosquito Spray, with active constituent:
    50% w/w, 55% w/v Fenthion, 0.0-dimethyl 0 – (3-methyl-4-methylthiophenyl)phosphorothioate). Then realising it was obviously my Grandfathers as he was a butcher and had hias own slaughter yards and also a piggery. No I cant get this smell out of my room as this is meant for use in meatworks etc and should be highly concentrate. I used it in my house with no concentrate. I was told to try CLR as it is corrosive and maybe will draw it out of cement but it reacted frothing up but smell didn’t weaken. Tried water, detergent, ajax etc nothing is eradicating the smell. Some one told me lemon time but I don’t want to go in there and start scrubbing again as I have made myself feel ill a few times from the toxins.
    Please tell me there is a way to get rid of this awful smell without jackhammering the concrete patch where I used the chemical.

    • I doubt that the smell is the insecticide from your description. But the question is, what is it?
      So, in order, try the following:

      1. Alkaline Cleaning. Spray some Easy Off oven cleaner on it. Wait 15 min then give it a bit of a scrub and wash off.

      1a. Alkaline salt. Same approach with neat ammonia (any sort)

      2. Weak Acid Cleaning. Tip some vinegar onto it. Leave for a while then hose off.

      3. Strong Acid. Use Hydrochloric acid. Try 1 in 3 initially. The cement will fizz – the idea is that you dissolve the cement under the stain. If the stain has sealed the cement you can up to use the HCl neat (but make sure it’s well ventiulated – HCl fumes aren’t toxic but they are an irritant).

      4. Enzyme Cleaner. Spray some White King Stainlift onto it and leave it for 15 min. Hose off

      5. Solvent approach. Acetone.

      6. Oxidation approach. Bleach (12% strength from a pool shop)

      7. Paint stripper. Get some Citristrip from Masters.

      One of those should work

  49. I used aluminium foil on windows to darken a room, now that I have removed the foil I have strange marks on the window. Have tried vinegar, metho, baking soda and a other supermarket purchased cleaners. Nothing is helping budge the marks. Any suggestions?

    • Vinegar is too weak, baking soda won’t clean anything, and metho is the wrong stuff. If anything will work, hydrochloric acid will do it. Make up a 1:1 solution, soak some in a rag and rub it (wear gloves). If that doesn’t do it, use it neat, but do it in a well ventilated area as it has strong fumes

  50. Hi Dr,
    We just moved into a nice apartment just a few years old. It has honed bluestone tiles on the kitchen and bathroom floors that we assume were once sealed although not sure. There are some stains (cooking in the kitchen, not sure in the bathroom) here and there that don’t come out with a steam mop. Any ideas? Many thanks

    • For the kitchen use Easy Off oven cleaner (or any oven cleaner). If they aree cooking stains they are probably oil/grease. For the bathroom, use BAM Easy Off bathroom cleaner with sulphamic acid (I forget the actual name of the product)

  51. HI Dr Chemical
    I have jarrah Low Gloss Polyurethane finished floor boards. 2 years old.
    Problem: Dog spittle. Literally.
    Our dog lies in a few favourite spots and of course dribbles consistently in those. He also dribbles randomly elsewhere – especially if he thinks food is coming his way!
    The result is hard spots of “stuff” as it dries up, that do not get removed with a simple mopping. It doesn’t break down.

    Currently I use a well known and expensive microfibre mop. They claim you only need to use water. Sorry but it doesn’t cut it!

    Generally, when I mop the floor ( with or without vinegar, methylated spirits or detergent) there must be general grease as well, because you can see lack of emulsification: rather than a smooth wet finish all over, there are areas that appear dry. What’s going on with that?

    Back to the dog: I suspect the spittle has protein in it? Is that the problem? What breaks it down and what could be used on my floor??


    • Get some White King Stainlift – it’s a laundry prewash that uses enzymes. Spray it on, leave it for 10 minutes or so, and then wipe off with a sponge. Alternatively, any laundry powder used as a paste with a sponge or scourer should do it. Also in general terms, the best off-the-shelf for cleanig floors is ammonia – about 1 part in 50

        • Hi Dr Chemical
          your advice was spot on!!
          We bought the Stainlift, and it does lift the cruddy dog spittle! There is a bit of scouring required, but very gentle and not enough to scratch the floor, as I have unfortunately done previously.

          Ammonia! Brilliant! It leaves a smooth swathe of fluid across the floor and cleans more than anything else I’ve tried. It makes me wonder if the expensive stuff I’ve tried before, is just ammonia with eue-de-almond-essence mixed in!!

          Cheers, and much appreciated.


          • There is a brand of floor polish (in a yellow bottle – Long Life I think) that is designed to be ammonia soluble. So if you want to polish the floor, and then restrip it later, it works a treat. But it says that on back of the packet (about the ammonia). Yes you are right – a lot of floor cleaners are simply perfumed ammonia. Personally I like the smell of the ammonia itself – it has a very “clean”smell to it

  52. Think I asked a question in the wrong section so I have re-posted.

    Love your site!

    Some help please. My bathroom basin which is about 20 years old and I assume made of vitreous china has suddenly developed grey hairline “cracks”. I’ve tried all the usual supermarket offerings and nothing works. I don’t think they are acutally cracks but maybe some sort of mould in the surface of the china. Is there anything you can suggest?

  53. I spilled about 8 – 10 litres of petrol on a grassy area in my yard. I live on an elevated block 10 metres above a tidal creek. The petrol was giving off heavy fumes so I poured dishwashing liquid on it, about 300ml and then hosed the area with water. The next day there is a massive green slimey slick on the creek mud bank and creek retaining rock walls approx 1.5 metres wide and 40 metres long. Is it likely this was caused by the petrol / detergent mixture? If so how can I clean it up or will it eventually disappear or dissipate as the tide comes and goes?

    • It’s a bit hard to tell without seeing it, but in general terms its bark is probably worse than its bite. Moreover, I suspect that it’s mostly detergent. That is, it looks worse than it is. In any case its not a huge amount, and the combination of water, sun, oxygen and bacteria will soon take care of it

      • Thank you, you’re right it has become less noticeable after a few days. The petrol fumes however seem to have gotten worse. I expect they will eventually disappear once the fuel has totally evaporated.

  54. Hi Dr Chemical,
    I did decking oil spray on fence.Due to wind some decking oil came on my car. Please help me how I can remove decking oil safe from car

  55. Dear Dr Chemical

    I recently bought a Match Pewter butter dish that comes with a glass insert. The company claims that their Pewter products are lead free, FDA approved and food safe.
    Well, I have kept a block of butter in that butter dish but the pewter lid appears to have left a film of black/grey powder on the butter. Is this toxic and should I be concerned? Would most appreciate your advice. Thank you kindly in advance.

    • Pewter does not contain lead anymore, so that part is believable – it’s mostly tin, which is not toxic. But I have no idea what the grey powder would be. But if you just scrape it away it should be right to use.

  56. Hi Dr Chemical
    We have bought curtains with rubber backing or blockout and when I washed on Gentle cycle with cold water and wool wash the backing came off and now you can see through them. When we first got them they smelt strongly of a chemical on the material. Is it possible that chemical mixed with water could have taken the back off the curtains (in only some areas).
    10 to 20 years ago I had these curtain and they washed beautifully. Would you know the chemical they use on these curtains?
    Thank you

    • No I don’t, but rubber comes in many different grades. It’s probably just a cheaper grade of rubber than the ones you had 10 or 20 years ago

  57. We had a strong smell on curtains from Spotlight. They won’t tell us what it is but I think it may be Formaldehyde. Can Formaldehyde mixed with water in washing curtains destroy the rubber backing?

  58. Hi, love your website. We have a problem with white stains on our brick walls from aluminium window frames corroding and leaching white residue. We used to have a garden against the wall and the sprinklers sprayed onto the windows. We have tried hydrochloric acid, no luck. Any suggestions?

    • The white stuff is Aluminium Oxide, an extremely stable compound that is known as Alum. Try Easy Off Oven cleaner. The caustic soda may shift it. Spray it on, wait 10 minutes then hose off. If that doesn’t work, nothing will

  59. Dr Chemical,
    I am looking to purchase a lift chair for a super senior. There is incontinence risk and I want to select the best material to deal with urine risk. I am thinking real leather and treating it with either a silicone polymer spray or an acrylic co-polymer spray.

    Do you agree with leather as the best choice? If so which waterproofing spray would be more effective for urine which I think is generally acidic.

    • If you’re looking for something soft from a comfort standpoint, then yes, leather is your best choice. There is no one-off, absolutely foolproof way of waterproofing it, however. But it can be effectively waterproofed by regular liberal applications of Dubbin, at least once a month, or more frequent as required

  60. Greetings,
    I have an electric Guitar, wood body, stained and laquered, that has been polished many times over the years with Mr Sheen. This seems to have created a build up, which itself has scratched and become blotchy.
    How can I remove the coating of Mr Sheen, so I can polish with a new polish?

    • In order of increasing aggressiveness I’d go Shellite, xylene, and acetone as required. You also might want to consult a spray painter, as they have to do this all the time (getting Mr Sheen coatings off cars that they are respraying)

  61. Hello Dr. Chem,
    I am wondering what might be destroying the foam rubber layer above the hard rubber of my shoes, shrinking them to the point that they detach the rubber soles? This only happens in one area of my garden next to the fence on the other side of which directly sits a neighbors hot tub. Also, the neighbors recently discovered a sewage leak under their house that is about 20 feet from my fence, but has appearantly been going on for a couple years. Could either of these be the reason? I should also point out that this is the same area that I dispose of a decent amount of sawdust, comprised of a wide variety of species of wood nearly all thoroughly dry. Maybe this? I just got a new dog and am obviously concerned about this. Thank you so much in advance for any insights you may have!

    • There’s almost certainly no chemical culprit – probably just cheap shoe design and manufacture. I have the same problem. They just don’t make ’em like they used to

  62. My Husband that was highly infected with colon cancer with mets to other parts of the body, he was even given 6 months to live. God, life for the family was a living hell with sorrow in the heart, but today i shouting out to the world that the cannabis oil have save my husband from dying. he is still alive and we are in the 10 months. God is so great to the Faithful. Thanks to Mr. Gregory Turner that sold the Hemp oil for us that we used in curing my Husband. Once again I want to thank Mr. Gregory Turner for his wonderful Hemp Oil we are now happy family with my Husband back alive, strong and healthy. You can contact Mr. Gregory Turner on every medical issue on his email: for more help.

    • I don’t know, and without seeing it it’s a little hard to guess what it is. I’d be contacting the store you bought it from. They may refer you onto the oven company – they may know what it is. My guess would be that it;s something to do with the gas, but the oven company should be able to identify it.

  63. Hi there,

    A cleaning cloth with brasso got into the washing machine….and the smell is atrocious. I’ve done a few rounds of washing with bicarb and vinegar – but nothing is reducing the smell. Can you make any recommendations?



    • I’m not sure what the smell would be – probably ammonia I’d say, but if the only thing you’ve used is bicarb and vinegar I’m not surprised that it didn’t do anything. Bicarb (sodium hydrogen carbonate) is a weak base and vinegar (acetic acid) is a weak acid. Adding them to each other only neutralises them both, and it’\s a mixture that has no cleaning properties whatever. Vinegar is useful if you are cleaning an alkaline stain like soap scum on your shower screen, but bicarb won’t clean anything. It’s a good deodoriser in some cases but that’s it.

      If you do a wash with hot water and a premium brand detergent that should take care of the problem. The ammonia will be sucked up by the antiredeposition agents.

  64. Hi Dr chemical what would be the best way to clean bugs of the front of a car. There is so many products on market, I hope you can help

  65. Some of the washed clothes from my front loader washing machine are covered in a fine grey splatter.It looks like a stain but is not greasy. Any suggestions as to what is causing this? I have not changed my laundry powder recently. Thanks. Kerry

  66. I love science and those who understand it!!! I just read your post from Oct 17 and used metho to clean the silicone off the toy. Thank you for sharing your knowledge !!!

  67. Have you heard of oogoo? It is a diy mould maker made from cornflour and silicone that sets at room temperature. I have tried making it with par fix and selleys with very different results. The par fix tends to set too hard and the selleys hasn’t set at all. I have had one successful batch by reducing the amount of cornflour I added to the par fix but I feel like I am just stabbing in the dark as I do not understand the chemistry of what I am doing. Are you able to give me some guidance as to proportions of cornflour to silicone by weight? Websites I have looked at suggest proportions by volume but I think weight would be much more accurate as transfering sticky silicone from a measuring device is difficult. Also, can I you suggest a way to remove silicone from the plastic toy I was trying to mould and failed?

    • There’s not a whole lot of chemistry involved. The hydroxy groups on the cornflour hydrogen bond to the water in the silicone gel, thus reducing ts viscosity. The proportions are therefore entirely empirical. To get it off, metho or acetone will do it

  68. My son used oven cleaner to clean and shine his brush steel microwave and the stove top burner free oven. Both appear to be stainless steel. The microwave now has white film embedded into the steel around some areas but the oven somehow was not affected. It appears to be a chemical reaction.

    • I’m not sure what the white marks would be but Brasso should restore the surface – it’s still the best metal cleaner around

  69. Hi,

    I attempted to clean the inside of the dryer with household all-purpose cleaner. I sprayed the inside, let it sit, then started the dryer to more thoroughly clean. When I stopped the dryer, there was visible residue still present. I wiped it, and the wipe turned a reddish-brown color with some yellow as well (the cleaner is yellow). were the brown stains, etc. caused by the cleaner, or could there have been dried blood/fresh blood in the dryer that i didn’t see before? It’s a community dryer, so I’m i’m worried. I also have OCD, so I’m hoping there’s a simple chemical explanation for the brown and reddish stains. Thanks for your time.

    • I need some more details on this. Is it a clothes dryer? Why did it need cleaning? What sort of residue was it? What sort of household all-purpose cleaner was it? My guess would be that the red-brown is iron, but I need more details, such as where you live (town or city) and how much you know about the water quality

  70. Hi Dr chemical
    I have an old power point that has paint stains around it and have used a paint stripper to get majority of paint off but i still have small bits left on the power point and was wandering if rubbing alcohol would work to get this off.

  71. Hi good day, i just wanted to ask about what chemicals that can dissolves concrete cement mixed with resin ceramic & steel powder…Is there any mixture of chemicals that penetrates and what’s the ratio…
    Thank you and more power.


    • If anything will do it, it’s hydrochloric acid, but it will dissolve the steel too, although not as quickly as the cement

  72. Hi ,i have limestone concrete around my pool area and it is splashed up my limestone walls how do i clean this of with out damaging my walls,the wall are a different colour to the concrete ,i have tried a wire brush but this leaves marks on the wall ,also tried CLR stain remover did not remove anything ,Can you help me

  73. We live in a rural setting in Serpentine WA. We use ground water for window cleaning . This water is hard and leaves dry calcium type marks when the water droplets dry. What can I wipe over the glass to remove water droplet marks before cleaning with general glass cleaner. General cleaner does not remove with out many /many hours of hard rubbing.

    • Any acid or acidic cleaner will work. Try the BAM Easy Off (with Sulphamic Acid) or any other hard surface or bathroom cleaner that has “XXXXXXX acid” listed on the ingredients

  74. whats the best way of getting rid of ants in the home. they are in my sons bedroom & they get thru the holes in the window frame, not sure why in Qld we have window with holes in , im originally for England, where the whole house is sealed both doors & windows. I’ve tried ant sand, ant baits peppermint, vinegar,borax, & a few other mad recipes, wirh no sucess, I’ve been online & some people say find the nest, unfortunately i cant find it, its driving me absolutley mad. hope you can help

    • Try Ant-Rid. It’s a syrupy substance that you squirt into little pools along the ant trail (inside). The ants gather around it, eat it, and go back to their nests to die. Also Mortein make Ant Baits that are probably worth a try

  75. I spilled about a half pint of clear silicone grout sealer (like water) on my new gray (salt & pepper colored) carpet. I immediately toweled up what I could and then went over and over the entire area with with my carpet cleaner. Is there anymore I could do, and will the new carpet be ruined or stained?

    • Buy yourself a 2L bottle of metho. Cover the area with a thick cloth and soak it with the metho. Leave it for a few hours, tipping more metho on it now and then to replace what may have evaporated. The metho will cause the silicone to swell up and you should be able to peel it away from the carpet

  76. Hi Mark,

    could you please advise on how to clean the BBQ. I used Sodium hydroxide (thinking it is stronger than sodium carbonate) but didn’t work so well. Why is this. Are the BBQ cleaners the best way to go here?

    Thank you

    • Yes sodium hydroxide is stronger than sodium carbonate and is the active ingredient in most BBQ and oven cleaners. Maybe you didn’t leave it to react for long enough

      • Thanks Dr chemical, yeah I think you are right, the sodium hydroxide in the water was runny… The foaming action of BBQ cleaners seems to keep the active ingredient on so it has time to work.

  77. I used aluminum foil to block light from windows in our new house. When we removed the foil it left behind a stain which appeared impossible to clean. The regular glass windows had a white coloured stain but the ‘Low E’ glass at the front of the house had a dark brown stain. I discovered that a product called ‘Good Off’ combined with a green scourer and lots of very slow scrubbing got the white staining off. However, it will not budge the brown stain. I have tried various chemicals including nail polish remover, turps, metho etc.

    • You need an acid on that. Get a 1L bottle of hydrochloric acid from the hardware store, and then, wearing gloves, moisten a Chux or similar with the acid and try rubbing it. If that doesn’t shift it, try Easy Off oven cleaner (spray on and leave for a while). Al;uminium is soluble in both strong acid and strong base, so one of those should work.

  78. Hello,
    Could you please advise me how to remove bat guano from a garage roller door. I can remove it when it is quite fresh but if it has been there for a while the white patches do not come off.

  79. hi Dr

    I got a job to clean trucks windows at a coal mine, they are affected by coal ash + limestone hence making windows dull. i want to know which chemical or any product to use to clean those windows.

    • If it’s limestone then you want an acidic cleaner. Look for a bathroom cleaner with sulphamic acid as one of the ingredients. If not, any other acid will do, or even vinegar. Then use Windex

  80. I can’t get on my knees no more to clean my lanolin floor I am 64 . So I bought the Bissell steam mop. It doesn’t clean like I would like it to. What can I put in it to get my floor sparkle again. I sure hope you can help

    • The best chemical for cleaning floors is ordinary old ammonia (any sort will do) with an ordinary mop. About 1 part in 50 is plenty. The good thing about it is that it evaporates afterwards, leaving no residue.

  81. I am hoping you or anyone can me…. I am trying to restor an old vanity set which the pink enamel has become unglued. I do not want to get it wrong as they were my grandmothers… please help

    • So you want to glue pink enamel back on that has been lifting away from timber? I’d use a contact adhesive on this, such as Kwik Grip

  82. Hi Doc,

    Recently you recommended ammonia for general cleaning, and I wondered whether it would be suitable for cleaning windows?

    Peter Bull

    • Yes it’s not bad on windows. It’s a simple QAC, like other window cleaners such as Windex. The idea behind a QAC is that they leave a positively charged coating on the windows, so they repel the (positively charged) dust

  83. Hi Dr Chemical,
    I am looking for something to remove stains from a clear plastic café blind. It has been rolled up for the winter on a timber patio. When unrolled it has a thick stain along it’s length that I cannot remove with the cleaners I have tried. It also has some timber coloured stains on it. Can you suggest any solvents that may help with this problem.
    Thank you.

    • That sort of general grime is easily removed with an alkaline cleaner, and the easiest ones to use are oven cleaners. Any one will do, but I like Easy Off as it sprays a fine mist. Spray it on, wait five minutes, and then most of the marks will wipe off with a wet cloth or sponge. If this doesn’t get the timber stains off, try a dishwashing powder made up as a paste and rubbed in with a kitchen scourer. Alternative approach is metho, or if that doesn’t work, white spirits or shellite (but they sgouldn’t be necessary.

  84. I have truck rims (i believe composite) that no store product has been able to clean the embedded brake dust off (also tried Brake-Kleen with barely any results).
    I tried using xylene on a rag and it removed the lighter brake dust easily and if i kept a heavy spot dampened with a rag it started to remove it also.
    My question basically is, I am concerned that the xylene will run off onto the tires.
    Can/will xylene damage the rubber tires? (i would be using a tooth/parts brush to scrub with). Can i just rinse with water to help dilute or wash off the excess xylene?
    P.S. Tires are new (200 miles)

    • No the xylene will not damage the rubber. For getting the brake dust off, try Brasso. After 50 years it’s still the best metal polish around. Alternatively, try Citristrip (from Masters) – if the xylene works, the Citristrip will work better

    • I’m not sure whether you mean hand washing or machine washing. For hand washing use Morning Fresh, and for machine washing you could use washing soda. It won’t work quite as well as a premium product and it will leave streaks on glassware and cutlery, but it’s cheap

        • I’m not sure what you want to clean out of your dishwasher. The premium brands contain builders and chelating agents that stop the buildup of minerals, so try one of those if you have been using a cheaper one. Or add a rinse aid if you aren’t using one – that’s your chelating agent

          • Thanks for your suggestion.. that raises a question do we have to actually clean dishwashers.. i use finish tablet for dishwashing..


          • Actually, bang on cue, I saw an ad tonight for a Finish product that is specifically designed for cleaning dishwashers. That was good timing, wasn’t it?

  85. Hi Dr
    I have a house with an acrylic render textured frontage. Years of water trickling down from breaks in the cappings in a few spots have left accumulated water stains down the walls. I’ve tried blasting it off with a high pressure water spray but the residue won’t shift and looks unsightly. Although the walls are a light grey colour I’m nervous about using bleach etc. Any ideas?

  86. I also have an other issue.. my patio tiles show white crystalline deposits on surface after a rain.. possibly efflorescence.

    Any cleaning product say acidic..


    • Efflorescence is very hard to remove chemically. I’d use an abrasive paste cleaner of some sort on that and just rub it off. Kitten #3 Cut and Polish should work – it woin’t hurt the tiles as they are much harder than paint

  87. Hi

    We have dark jarrah flooring and it shows every dirt and most annoying is the foot prints when we walk on it.. could you suggest a cleaning product and method..pls. currently i use methylated spirit with water.

    • Ammonia is a good option. About 1 part in 40. Just mop it on as per normal. There is a characteristic smell which will evaporate afterwards.

        • Hi Dr chemical

          Before using Ammonua for cleaning floors jaf a quick look in google and most suggest not to use ammonia.. A bit confused .. could u help..

          • Nothing to be confused about. Unfortunately there is a lot of wrong information about cleaning about, due in a large part to Shannon Lush. There is no reason why you can’t clean your floors with ammonia

  88. Hi Dr Chemical,
    I have blackened areas (assume it is mould) on brickwork at my home. It mainly appears on brick pillars (especially the top area) and covers a brick letterbox, it is always worse in winter. The bricks and mortar are cream in colour. I have tried vinegar using a brush – this only made a slight improvement. Can you suggest a way of removing the mould please.
    Many thanks.

    • Vinegar is far too weak. The good news is that you can try anything on it and you won’t damage the bricks. You could hit it with pool bleach (12.5%) or hydrochloric acid (hardware shop). They will both kill the biomass, but not immediately. Give it a couple of days after treatment, then blast it off with a high pressure water cleaner

  89. Hi, We have just completed a bathroom reno and have Kerlite travertine floor and wall tiles. What is the best way/product to clean and keep these clean without causing damage. Also please advise the best and safest way to keep frameless glass shower screens and chrome taps and shower heads sparkling. Thank you

    • Anything metallic use Mr Sheen – that will both clean and protect. Same with the shower screen and wall tiles. The Mr Sheen leaves a silicone coating that will protect it against water. Don’t use it on the floor tiles, however, as it will make them slippery. For the floor tiles use ammonia (about 1 part is 50 is plenty)

  90. Hi,

    i work in the cheese plant and after a days production we doing a CIP of all the pipelines funnels made of SS 316 L using Chlorinated Alkaline cleaning agent ( 0.4-0.5% ) and additive chelating agent with water pH@ 6.8 and heating up the solution to 85 deg cent.Recently we noticed a black stain on all the surfaces after cleaning and it simply doesnt go off by severe hand rubbing. Any clue as to how to get rid of the black stain. we had tried out Nitric acid and it wont work.



    • It’s an oxide of some sort. It can be removed with the right metal polish, and believe it or not, nothing is better than Brasso. Alternative would be Kitten #3 Cut and Polish (or any other automotive cutting compound)

  91. My husband used kitten cut and polish liquid on our car. He got it on the vinyl and rubber and we can’t remove it. Any ideas?
    Thanks so much

  92. Hello Doctor Chemical,

    First of all, I want to congratulate you on your excellent website. I love the fact that it is based on science, not the mumbo-jumbo nonsense that seems to permeate so much of the public discourse (e.g. Paleo diets, anti-vax, climate-change, etc.).

    I have recently installed a new glass shower screen and want to keep it in pristine condition. Other than rinsing it with water after each shower and then wiping off the water, is there anything else that I can do? Is it a good idea to apply Mister Sheen to a new glass shower screen, or is that only for shower screens that are etched?

    Thanking you in advance,

  93. Hey I have just used the dettol bathroom foam on my friends bathroom that he just paid a lot of money doing. And I left it on for 5 minutes like it said and it seems the tiles look like they have cracked from underneath? What should I do? I’ve ruined his tiles!!!


    • No, you haven’t. All it is is a pretty standard disinfectant formula of QACs (benzalkonium chloride probably) and there’s no way in hell that would damage tiles. The whole point about tiles is that they are ceramics which are resistant to virtually everything (chemically). I don’t know what the marks are but it has not been caused by the foam.

  94. My dining table has a marble top. My mistake I attempted to clean it by using Harpic. It did not clean and has left a very bad mark on the table. What should I do to clean this stain and make it clean.

    • What sort of Harpic and what do the marks look like? The good news is that marble is very chemically resilient, and you probably haven’t actually damaged it

  95. Hi, when i was away from home, my son urinated on our brown leather sofa & didn’t tell us. he tried to wipe it up & then covered it with a blanket we use when it is cold. I’ve tried to clean it but, the stain has turned green, and has started to crack. i any help you could give would be very much appreciated

    • No magic answers to that one I’m afraid – leather is porous and it has sucked up the urea, thus causing the green stain. All I could suggest is some brown shoe polish. I doubt that it will restore it fully, but it will moisturise the leather, and may go some way towards reversing the cracking and covering the green stain

  96. Hello Dr, We live in Perth, the water is quite hard and leaves all my
    towels and napkins rough and hard, we have to replace our towels more frequently even if they are in good condition, only because they are quite hard and rough on skin, can you please help me to solve this problem.

    • Yes, switch to a premium brand washing powder, such as OMO, as they contain builders that will complex the minerals in the water. And wash in warm or hot water

      • Thanks for your response, in past I have tried OMO but can’t remember if it helped with softening the towels, as I have this on going complaint since we have moved to Perth. Also would like your help on how to choose a right shampoo and conditioner, again my hair is very dry and frizzy, and don’t like to use straighteners regularly, what products can help me.
        Highly appreciate your reponse.

        • I can’t help you with specific comments about specific brands of shampoos, but if you use a non-soap product for washing (such as Dove) then you can use it on your hair as well. The traditional shampoos are highly alkaline, like any soap, and the job of the conditioner is simply to neutralise the pH

  97. Hi and thank you for all the help you have provided my family so far. We have one of those automatic esspresso machines and the descaling solutions are expensive, can you suggest a better way to descale my machine, i.e parts ratio to ect of whatever you suggest
    Than you

    • A cheap alternative is vinegar – soak it for half an hour or so. Another alternative is CLR – it’s a little more expensive, but will do a better job. And the good thing is that you can reuse it. After soaking in the CLR, tip it into a container, and keep it for next time you need to descale. Eventually it’ll be spent and you’ll need to replace it, however.

      • Hi Dr Chemical, won’t CLR damage the seels or internals, the bottle I used from the manufacturer said it contained citric acid, lactic acid and something noncorrosive

        • No – the active acidic ingredient in CLR is glycolic acid, which is a weak acid like citric and lactic. But if you wanted to use lactic acid you could try Spray and Wipe (I think) which uses lactic acid as the active ingredient (look on the label to confirm). But vinegar will also work. The non-corrosive ingredient would be EDTA (a chelating compound), so it would be a more effective reagent than any of the acids, but vinegar used on a regular basis will work – you just might have to use it more frequently

  98. Dr Chemical,
    We have had our floors sanded, the smell was terrible. We were only told to make sure food stuffs in our pantry were sealed: anything open had to be removed. But the rest were to be ok, including things in our wardrobe and draws. On our return the smell went though EVERYTHING- including what was in the plastic containers with lids (Sistema brand ) My question, is the water based polyurethane vapours absorbed by plastic, silicone and wood? Do I throw it all out?
    I have tried to research this without success, I hope you can help.

    • The smell would not be polyurethane as it is a polymer and therefore non-volatile. Rather it would be the various catalysts and solvents used in the polymerisation process, some of which may indeed be harmful. So I wouldn’t be eating any food in them. But the good news is that if they absorb easily they will also desorb easily. Put the containers outside in the fresh air for a week or so and you’ll find that the smell will be gone, and they’ll be right to use

      • Thank you so much for your help. I really appreciate it. Could you tell me if unopened packets of nuts, cake mix, tomato sauce(plastic) bottles, packets of spices, wine-both corked and screw top would also be affected?
        More importantly my daughter has 3 months supply of contact lenses. Do I throw them out?

  99. Hi Mark

    My father Scott has emailed you privately as our first email to you on this web site did not seem to reach you. My question to you is the use of Olive Oil on Expanded Polystyrene Foam (EPS). This level of EPS that i am doing some test on is in Motorcycle Helmets. I am currently using the highest grade of refined unflavoured pure olive oil possible. This type of oil is commonly used for cooking in deep fryers (fish and chip shops). The olive oil in my case is being applied (immersed, soaked) into the EPS allowing the oil to filter its way through any potential crevice or void areas within the EPS foam. This process is only being used on potentially damaged helmets after an accident and the oil help the process of x-raying as it improves the level of contrast. My issue is once the oil has been applied, the X-ray image has been taken, what is the best and most effective way to remove the oil without damaging / degrading the EPS foam. My father has emailed you an attachment listing the chemicals that will and will not degrade EPS. Some people have suggested the use of BiCarb soda, some say the use of a degreaser (dishwashing liquid) and i think i read somewhere you mentioned soda ash. Maybe its a combination of all of them. The issue here is the removal of oil from very small areas and the inability to squeeze out the substance like you would a sponge in soapy water.
    Look forward to your reply

    Brayden Robinson

    • Bicarb won’t work – contrary to popular belief it has virtually no cleaning properties whatever. What you need is something highly alkaline. My choice would be Easy Off Oven Cleaner, as it sprays a fine mist of caustic soda. Spray it on, wait 10 minutes then wash it off. Or the stuff you sent me in email that contains the silicate would work too – this is a common ingredient of aqueous (alkaline salt) degreasers. The mechanism is saponification – the hydroxyl ion is a strong nucleophile that attacks the ester linkage, thus converting the fatty acid chain to a soap. That’s why it washes off in water. For a solid surface soda ash will work too (used as a powder cleaner and made into a paste)

  100. Dear Mark,

    Re: Your post dated November 28, 2014
    “How to fix your own teeth”

    Can i use Selleys Knead-it Aqua instead of multi-purpose.?
    (hard to get moisture away from wisdom tooth)

    Even though i understand the end product ‘thermoset polymer’ is
    inert and chemically safe;

    Are you sure it is safe to put in your mouth while it is going through
    the curing process. ?

    The reason i ask is i did a test piece first, to check the mix,cure and
    hardness timing.

    During this test i noticed a slight to mild vapour (hard to describe),
    i also tested the material with my tongue at various stages of the
    process resulting in a mild to strong bitter taste.

    Both of these, smell/vapour and taste i have never encountered before
    so i was not game to proceed further without your advice.

    Just to let you know, i was eating some popcorn and suddenly felt
    a crack in the back of my mouth, half of my lower wisdom tooth had
    broken away.
    No pain and the rest of the remaining tooth is strong and healthy,
    however the broken tooth has a sharp edge all the way down the vertical
    edge that cuts painfully into my tongue.
    Drinking,eating and talking is absolute murder.
    I have tried, sugar free gum and blu-tack, both work to stop my tongue
    from being cut up to the point of bleeding, problem is they will not
    stay in place for me to eat/drink.


    I guess at the end of the day it comes down to this question,

    Are the vapours or tastes given off during the chemical curing process safe. ?



    • Yes it’s perfectly safe – it’s an irritant but that’s all. It’s neither dangerous, toxic nor poisonous. BTW the repair I did is still holding. The aqua appears to have a longer setting time, which may be a little impractical. An alternative approach is to use the general purpose knead it even if you can’t get to the tooth to dry it. If it then falls out you have a moulded repair that you just need to reattach. This can be done with super glue, as super glue actually relies on moisture being present for the bonding process.

      • Hi Mark,
        Sorry for being late in my reply, computer probs :)
        Re: Irritant and safe for use.
        Thank for the info.

        Re: Your earlier repair still holding.
        Great to here, gives me confidence to proceed
        hoping i have as much success.

        Re:Auqa setting time/impractical ?
        You may be correct, during my test the timing of the mix/usage and cure were at least double that stated
        however i sort of expected that due to low ambient
        temps. (18deg.C)
        Will give it a try anyway.

        Re: General purpose knead/super glue.
        Fantasic idea as an alternative / plan B.
        I will give the Aqua a go first and let you know how
        i go.
        I will attempt it within the next day or so in an ambient
        temp of 30deg.C for faster cure time.

        I have found a temporary fix while waiting for your advice;
        I have managed to use the KFC wipes that they supply
        with fast food chicken take-aways, i just cut off a piece
        and wrapped/jammed it into the affected area and it
        Not a great fix but it’s bought me some time.:)
        Thanks a lot for your help Mark it is greatly

  101. Hey dr.
    I had this old chips cardboard box sitting on my wardrobe. I accidental sprayed some hairspray on it and stuck it to the wardrobe. I left it there for a couple of hours. When i pulled the box out, parts of the box got stuck to the white wardrobe. Do you have any idea on how to get rid of the excess blue colour paper stuck to the wardrobe?

  102. Hi, I have a 8 mths old puppy and he has started to pee in the door/flyscreen track, I have used all sorts of products, bleach, disinfectant, scrubbed it and poured boiling water over it but the smell doesn’t seem to be moving, Please can you advise me what to use to make my home smell good again.
    Thank you

    • The smell in urine is amines. There’s a couple of approaches you could use. Vinegar is a good option as the acetic acid will neutralise the amines and should eliminate the smell. Alternatively if it’s on an exterior surface you could use heat on it – like a heat gun. The heat will cook the amines and volatilise them. It’ll smell worse initially, but then the smell will disappear

  103. Hi , My daughters dress is 100% polyester and some chocolate from a chocolate fountain splashed on it, the dress says dry clean only but the dry cleaners said there was no guarantee that they could get the stain out. What do you suggest.



  104. Hi Dr Chemical
    I have just recently discovered you website and its already helped me with cleaning which I hate, but now I dont! well not so much. Can you tell me the best way to clean a large area of ceramic tile floors. I’ve moved to qld from the UK & aussie houses have massively large ceramic tiled floors that seem to never end. I vacuum and steam them but they take ages to dry. when i first moved into the house I had the floors & carpets professionally cleaned & the man told me the best way to clean floor tiles was with neat chlorine bleach that you get from the pool shop. would you agree with that or would you need to dilute it. do you have any easier or better solutions.. Thank you so much, Diane

    • I have a Karcher steam cleaner where you can vary the steam settings so that minimal water is used. This results in a very fast drying time. But in terms of a traditional mop and dry, the best off-the-shelf chemical is ammonia. Half a cup in a bucket is plenty, and the ammonia will evaporate after it dries

      • Thank you I will try that, I cant find plain ammonia I can only cloudy ammonia. does it make a difference. & would you know where I can buy clear ammonia.

        • Cloudy is fine. They just put a bit of detergent in there to create the cloudy look, as years ago they made ammonia from coal tar and it had a cloudy look. Bit silly really

  105. Hi there,

    Just wondering if you have any ideas on how to get condy’s crystal stains out of the carpet?

    • It’s easy to get out but only if you have the right chemicals. You need to create an acidic environment then hit it with a reducing agent. The acid part is easy – just pour some vinegar onto it. But the reducing agent is alittle more difficult to come up with – sodium thiosulphate, ferrous sulphate, or sodium oxalate would all do the job nicely, but none of them are off the shelf chemicals. Let me sleep on it and see if I can think up a reducing agent that would be found in the supermarket.

  106. Do you know anything about Great Stuff expandable foam sealant? My cat may have ingested a tiny amount and has been sick for a few days. I find NOTHING about the product in its wet uncured form but in its dry cured form it is non toxic but could cause gastro irritation and possibly blockage. I’ve been to 2 vets this weekend and neither suspect blockage and xray looks like gas. The tiny amount of thin poo I’ve seen is suspiciously the same color as Great Stuff though. Vets don’t seem to be cooperating with me and I can’t find any leads. Dow is closed til tomorrow so I’m just trying to get some answers sooner. Thank you so much.

    • It’s polyurethane, which is inert – that is, unreactive and non-toxic. I can not advise you on what to do with the cat, but my guess would be that it will eventually pass through. I once accidently ate some polyurethane packing chips and they didn’t cause any ill effects

  107. I noticed your article “My Favourite Products #4: Ajax powder Cleanser” where you speculate that Ajax powder is a repackaging of the old Bon Ami cleanser.

    I agree that Bon Ami doesn’t seem to be available any more in Australia, but the US website at makes its constituents clear: originally tallow soap with the addition of feldspar as a gentle abrasive, which is still made today. But Bon Ami also has a newer formula product, containing plant-based cleaning agents from coconut and corn oils, plus feldspar and limestone as abrasives, and soda ash and baking soda.

    The Ajax Australian site at lists slightly different ingredients: calcium carbonate as the abrasive, sodium carbonate as “processing aid” (not sure what that means), sodium dodecyl benzene sulfonate as cleaning agent, fragrance, preservatives and dyes.

    I’m not a chemist, so perhaps you could expound upon the differences, which seem slight.

    • tallow soap and “plant based cleaning agents” are essentially the same – bog-standard soaps. Sodium carbonate is a very good general purpose hard surface cleaner. But I think you’ll find they both contain calcium hypochlorite – powdered bleach, which is a powerful oxidiser. Ajax also contains copper, which serves the function of making it go blue when it gets wet. Nothing to do with cleaning – just marketing. People associate blue with cleanness (which is why toilet products are blue)

  108. What is the best cleaner for a marble benchtop?

    I know acids dissolve marble so have used washing up water containing calcium carbonate and detergent, and tried Ajax recently. Despite rinsing with water and great care, there are spots and rings etched into the surface. How can I:
    1 prevent more etched areas occurring?
    2 get rid of the ones already there?

    • No, acids don’t dissolve marble. I’ve used concentrated HCl on marble (on exterior surfaces) with no problems. Best general purpose approach is an oven cleaner. Spray a fine mist on, then wipe off with paper towels. Then finish it off with Mr Sheen – it’ll come up a treat

  109. Help Doc!

    My wife just bought a beautiful and expensive suede bag….we were told to lightly spray a waterproofing compound on it (read siliconized hydrocarbons), which we did. Unfortunately we have one area that got a spot that now looks quite oily. We are brushing the suede to bring up the nap, but anything else you might suggest? Spray the whole thing again and make it consistent?

    Yours in Chemistry,
    Paul R
    Houston, Texas

    • Suede is really tricky. If it was me I’d be figuring out what the solvent was that the silicone was in and spraying some of that on. Or choosing something what would resolubilise it and spread it out. Isopropanol would be my first choice, potentially moving onto something a little more paraffinic

  110. Hi Dr Chemical,

    How do I get aluminium foil residue off that is stuck on my windows?

    Thanks for the good work you do.

    • I’d be using a strong acid on that. If you have any Easy Off BAM with sulphamic acid try that, but I suspect it won’t be strong enough – you’ll probably need to use hydrochloric acid. Get a 1L bottle from the hardware store, and mix it 1:1 in a generic 1L garden sprayer pump pack. Then spray it gently on the aluminium. You should see it start to fizz. Leave it for a little while then spray a bit more. If needs be you can go up to 100% acid on it. It won’t damage the glass. Don’t worry if any runs off onto door frames – just wash it off afterwards and it won’t cause any permanent damage

  111. Hello Dr chemical,

    I am operating small cleaning company. we recently sign a contract with a restaurant.
    In that restaurant all the kitchen equipments are made of shine stainless-steel. To remove heavy rust, sticky sauces, oil, honey and other heavy stains, one of my cleaner had used degreaser and he used this heavy degreaser on all the stell surface. he thought it will shine but that degreaser left white marks on all the equipments and now restaurant owner is asking me to change all the equipments.

    I would highly appreciate your help and any solution for this particular problem

    Thank you for your help.

  112. Hello Dr. Chemical,

    How are you? I’m a senior taking Regents Chemistry and for my final assignment I’ve been assigned to write a lab report about removing an olive oil stain from polyester by using a solvent. I chose to use cyclohexane. For my assignment I need to ask an expert on stain removal some questions and I would love if you would be able to answer my questions.

    1.) I learned that dissolving works based on the chemistry rule that like dissolves like, but can polar solvents dissolve nonpolar solvents at all?

    2.) If an olive oil stain is left on polyester for a couple of days would that affect the effectiveness of a solvent?

    Thank you and I hope to hear from you soon.


    • 1. In general no, unless they contain either enzymes or surfactants. Or an aqueous solution of sodium hydroxide, but not because it dissolves the triglyceride, but saponifies it. But there are some solvents that are partially polar, in that they are miscible with water, that would dissolve the olive oil. Examples would be isopropanol, acetone, and d-limonene (the active ingredient of “orange oil”). These solvents are all short-chain, oxygen rich hydrocarbons. The carbon chain gives them a sufficiently nonolar properties to dissolve oils, and the oxygen allows them to be miscible with water. Cyclohexane would work, but would leave a smell on the clothes.

      2. Not really. Polyester would only have weak chemical interactions with the olive oil, and a few days wouldn’t make any difference.

  113. Hello Dr. Chemical;
    Thank you for your advise.
    After I sprayed the inside refrigerator with the bleach then a few days
    later with rubbing alcohol. Radar instinct when off. I asked on the
    web of mixing the 2 mixture and the chemical result of chloroform
    production??? Still a bit worry? The refrigerator hasn’t been opened
    in the last 2 years.. Fear of Health issues?!?
    Thanking you in advance.

    • I’m not sure I understand your question, but bleach and rubbing alcohol do not make chloroform. But just open the fridge and let it air – all the bleach and isopropanol will evaporate

  114. hello Doctor Chemical :
    Need your help please. Accidentally sprayed a while back Javex Bleach to
    kill fruit flies. Later on I Sprayed alcohol 50%. Still have fruit flies flying out.
    Read too late of Chloroform result. What do I do? Please Advise?
    Thanking you in advance for any help.

    • If you are worried about some sort of reaction between the bleach and the alcohol you have nothing to worry about. And I’m not sure what the chloroform comment is all about, but it is nothing like either bleach or alcohol.

  115. accidentally sprayed inside refrigerator with bleach to kill fruit flies later sprayed rubbing alcohol am i in danger? what do i do?

  116. Its 2pac paint, same as used on cars so I’m guessing it’s the same process. It’s left a cloudy finish on the door.


  117. We have recently built a new home with a 2pac kitchen with some doors painted in a darker colour. We have had to have one of the dark doors repolished due to a fault and the door is now left with looking slightly grey or cloudy. Do you think there is something we could do to bring the full colour back (maybe cut it back with polish) or should we have it re-painted?

    • I need more details on this – how was the door repolished? The best polish bar none is Mr Sheen. The best cutting polish is Brasso. If neither of those solve your problem you may need to get it repainted

  118. Hi Dr Chemical,

    I have been reading your blog for years and absolutely love it! When does your book come out? I didn’t realise the Q+A section gets updated so often, as I only subscribe to your new blog posts. It would be great if you had a weekly Q+A newsletter for subscription! I love that you de-bunk the cleaning myths (most notably the Shannon Lush ones that many take as gospel).

    Anyway, I have a big, bright red stain on my carpet, and I don’t know what it is. It looks like some kind of food dye, like from a red fizzy drink, not like a red wine stain. Can you please help me to get rid of it? I don’t know what the carpet is made of, as I am renting, and the stain has been there for about 12 months.

    Also, I would like to know if it is true that stains can ‘set,’ say if you leave it for a long time, or if you treat with other things first.

    Thanks, Doc! Looking forward to your reply!

    • The best thing for that is an oxidiser. Preen Vanish make a carpet cleaner with “Oxy Action” – that should do it for you. And yes, it is true that in general stains become harder to remove if they have been left for a while

  119. Hi Dr. chemical
    i got a question that i could not find an answer for, so i will appreciate it your help

    my question is
    a mixture of oil, water, alcohol and surfactant forms a turbid dispersion after a lot of shaking: 1- what its will formed. 2- and why its formed? 3- why its not transparent?

    • It’s not transparent because it’s an emulsion, and emulsions aren’t transparent. The micelles refract the light

  120. Hi Dr Chemical,

    We have a Front Loading Washing Machine. Despite many attempts we can not get rid of the black stains that accumulate in the bottom of the door seal.
    Is there anything you can suggest to remove these?
    Thank you in advance :-)

    • Not sure if you’re referring to black stains from the rubber or something else. If it’s the rubber, go to Masters and get a product called Citristrip. Follow the instructions and it’ll do the job

      • Hi Dr Chemical.

        Managed to find that in the paint stripper section at Masters. We’ve tried it a couple of times and it has lifted a little but the black marks are still there. These are on the rubber seal at the bottom of the door opening (where water gathers after the wash).

        • Righto, next step is chemical and mechanical abrasion, believe it or not. Either Ajax (or Bon Ami) powder Cleanser or Brasso. Both are excellent mechanical/chemical cleaners.

  121. On an international flight I had my leather jacket packed on top of my bag in the cargo hold. Something leaked during the flight and left what looks like an oil stain with black specks in it. Can I salvage my jacket?

  122. very fine somewhat sticky power substance reddish brown main entry closet on ceramic tile floor. what can it be ? keeps coming back. At first we thought termites but no openings can be found. Thank You.

  123. Hello the good Doctor!
    I borrowed a friends beautiful soft leather bag…and managed to get Invisible Zinc smeared on it. (It’s a thick sunscreen I was wearing at the time)
    It has left white stains, I’ve tried a leather conditioner but it hasn’t worked and I’m scared I will ruin the bag more.
    The only active ingredient in Invisible Zinc is “Microfine Zinc Oxide”.
    Can you help?

  124. Hi there,

    I have got some borewater stains on some cotton work shirts.

    Wondering if you have a magic solution to get this out…i have of course tried soaking and soaking and saoking all in SARD.


    • I’ve heard of borewater stains on lots of things, but not on shirts. Never mind, there are ways around that. Go to Bunnings and buy a product called Gelmac. It’s an 8% solution of oxalic acid, and if you soak the shirts in it, the stains will come out, and as it’s only a weak acid it won’t damage the fabric

      • Awesome thank you…..heading off to Bunnings now. I didnt mention that they were not white shirts they are coloured. Hope that doesnt affect it.


  125. Hi

    I have wash my car with soda ash , will it make it corrode , if it put in say 1 kg in 20 littres of warm water would that do it. I am in a complex where they dont like foam , and i have a big bag of soda ash which i use to clean most things .

    • There’s a person after my own heart – soda sh to clean almost anything! No, it won’t corrode your car, as it’s alkaline (not acidic), and so you can use as much as you want with perfect safety. Have a look at for some ideas on how to use soda ash

  126. Hi Dr Chemical,
    I was interested to read your article on the use of sodium percarbonate as a laundry pre-soak. I’d like to know what the temperature the ‘hot’ water be when using this chemical? (as our water is set to 42deg C). Also, could you comment on other applications for this product, such as for cleaning discoloured sandstone walls?

    • Hi Katrina. Great to hear from you. With sodium percarbonate it’s a simple case of the hotter the better, simply because it is an oxidiser. That is, its cleaning power results from its ability to smash to bits the large, complex organic molecules that most dyes are made from. If your wash is 42 degrees, you might want to consider an enzyme cleaner, as this is the optimal temperature for enzyme activity.
      For your sandstone wall, you’re better off with caustic soda. Make up a 1 or 2% solution, spray it on, let it soak for half an hour and then hose off. Best to use a high pressure washer with some caution as sandstone is soft and you’ll blow holes in it.

  127. I have just had a new house built by a builder and during the process the grano worker has left small amounts of grey concrete overspray on the existing color bond metal fence. What can you recommend to recover the dry concrete from the fence without damaging the color bond sheeting?
    Regards Greg

    • Easy, Hydrochloric acid. I’d use a 1:1 solution in a generic spray bottle. It’ll destroy the plastic trigger mechanism eventually, but it’ll last long enough to do the job. And it won’t hurt the colorbond. You could use the HCl neat if you wanted to.

  128. Hi Dr Chemical,
    We’ve just moved into a house which has a very strong curry/spice smell everywhere but especially the kitchen and living areas. These are tiled areas. What do you recommend to remove the smell altogether? I’ve read ozone generators can help but is there a chemical way to do this without machinery? Ideally we would like to get rid of the smell 100%… It really lingers.

    • I’d wipe everything in sight with metho. It’s an excellent general purpose solvent and would probably dissolve any residual bits of spice on any of the surfaces in the kitchen.

      • Thanks for your reply, should I dilute at all or just use 100% strength?
        Also, have you heard of a product called Nilodor? Do you think this would help with this kind of smell?
        Hereis the chemical details:

        Chemical CAS No / Unique ID – 000000-00-1,
        Percentage: <1%

        Ethanol/SD Alcohol 40
        Chemical CAS No / Unique ID – 000064-17-5
        Percentage: 0.5-3.5%

        Sodium xylenesulfonate
        Chemical CAS No / Unique ID – 001300-72-7
        Percentage: <1%

        Chemical CAS No / Unique ID – 007732-18-5
        Percentage: 90-95%

        Chemical CAS No / Unique ID – 009036-19-5
        Percentage: 3.0-5.0%

        Thank you!

        • Use the metho undiluted. I haven’t come across Nilodor, but it appears to be a mixture of two surfactants with a bit of ethanol and fragrance. It’s certainly worth a try. Let me know how you get on.

  129. Hi Doc!
    Great to see your posts for the new year! Love this site, and am subscribed on my feeds app!

    I clean my kitchen with a spray that combines methylated spirits, white vinegar and water. Is this OK? It’s pretty cheap and works well. I’m not poisoning myself, am I?

  130. Hi I need help with removing paint from some type of metal material. May be pewter or may just be metal. I can’t tell because… well it’s covered with paint. :) The problem is the item is an antique glass and some kind of metal substance ewer/claret. I think it is probably pewter and someone felt it wasn’t shiny enough so they used a silver paint on it. I need to strip to it’s original state without etching the green art glass it surrounds. Thanks in advance for any help you can offer!

    • Go to a Masters store and buy a product called Citristrip. Follow the instructions on the pack and it should do the job for you. Have a look on YouTube as well – there are a couple of clips of people using it.

  131. Hello Dr. Chemical,

    I washed a pair of (97% cotton, 3% elastane) pants with a multi-vitamin in the pocket. I now have lovely yellow stains on the pocket; probably from the B vitamins.
    I’ve tried bicarb and vinegar and Napi-san spray which has faded them slightly but they’re still fairly obvious.
    Any suggestions?
    Thank you.

    • Bicarb and vinegar have no cleaning properties whatsoever – you’ve made the mistake of listening to Shannon Lush’s amateurish advice. You want to get some enzymes onto that. White King Stainlift is an enzyme based cleaner that should do the job. Spray it on and rub it in with your fingers for a while. It’ll probably mostly come out as your body temperature is just the right temperature for enzyme activity. Then pop it in the wash (warm or hot water) and it should disappear. Rule of thumb – for food stains use enzymes, for synthetic stains use oxidisers.

  132. This is a question :

    I sprayed long life tile cleaner onto a marble floor & can’t get the spray marks out , please advise & reply as soon

    Have a good day

    M Gallon

  133. Recently I’ve been reading about turning waste plastic to diesel or other fuels. I’ve seen large commercial plants down to people with pressure cookers doing it at home on youtube and various places. My question is what are the key factors involved in the process, that if you could control would give you exactly the fuel you are looking for each time? e.g. diesel, gasoline.

    • The most I know about this process is that it is possible in principle. Given the complex nature of fuels, the process would be very detailed and technical, and I simply don’t beleve you could do it at home in a pressure cooker. Also, it wouldn’t produce petrol – it’d be diesel. Have you considered making biodiesel?

  134. Hi Dr Chemical,
    I have wooden floors which are finished with a very durable semi gloss. My clean spilt a mixture of ammonia and metho (uses on shower screens) over a large area. Initially there was a long whitish trail across the affected area. I found the damage hours later. Warm water did not remove and subsequent attempts with wood oils have not removed the original marks which can still be seen in certain lights from an angle. Will I need to have the whole floor resurfaced? Help!

    • Believe it or not, ammonia is your best option. Make up a solution that is about 1 part in 50 and mop the whole floor. If the white stuff came from ammonia, then ammonia should redissolve it. Also, ammonia is not the best stuff for shower screens – you need an acid. A cheap and cheerful solution is vinegar

  135. Hi
    I got ink on my shirt and only realised after I washed it. I tried using rubbing alcohol to get it off as per your suggestion but it doesn’t come off. Is it because I washed it or is there something else I can try?


  136. Hi Dr Chemical,
    Just wondering if you can tell me whether or not water with a reasonably high alkaline level (due to concrete sediments) may damage the paint on a vehicle (and only damage the clearcoat/topcoat not the base coat)?

    • It depends what type of paint it is, and how old the car is, but yes it’s poosible. An acrylic paint will be damaged but more modern two-pack formulations are much more resistant

    • Sprinkle caustic soda pellets on, then wet it with a minimum of water and scrub with a stiff brush or broom. Hose off, or better, use a HP water cleaner.

  137. Hello,

    I went on a camping trip recently and I opened up my canvas tent to see it was covered in mould….

    Any sugestions on how to clean without damaging the waterproofing?
    Thank you!

    • Best approach is to spray it with a 70% solution of metho in water (7 parts metho, 3 parts water). This will kill the mould and then you can brush it off, or blast it off with a good steam cleaner

    • It depends what the actual colour is, but I’d try soaking the effected part in Metho. If that didn’t work, try acetone. If that didn’t work, Orange Power Sticky Goo and Spot Remover (small orange bottle in the cleaning aisle). Or preen Oxy-Action powder would probably work (used as a paste like on the TV ads).

  138. hi,

    my mum used washing soda to clean her gas cooker burners and they have gone from being shiny metal with crud on them to being clean of crud but blackened? there must be a chemical reaction of some sort and i don’t know what to tell her to do next as she just wants them to be clean and clean looking (not black) help please?? i don’t know what the metal is sorry.

    • I see you’re in the UK. Here in Australia I would recommend Kitten #2 Cut and Polish (it’s an automotive polish available from auto accessory stores), but I’m not sure if it’s sold in the UK. If it isn’t, go into an auto store and tell them you want a cut & polish product that is designed for rejuvenating old paint. Or Brasso would also probably work – it’s an oldie but a goodie

  139. Hi dr Chemical!

    I love wool and woolen clothes (I have to, I live in Scandinavia!), and have just learnt about treating wool with lanolin. It sounds great as it is supposed to both strengthen and condition the fibers and make the clothes water and dirt repellant.

    I was just about to go buy some lanolin when I read that moths love lanolin. My wardrobe is already quite a feast for them and I do not want to make my problems any bigger. Luckily the winters here are cold and I periodically move all of my wool out on the balcony for some frost treatment.

    Researching the Internet about every second source says that moths love lanolin and every second says that lanolin protects against moths. I am really confused and was hoping maybe you are the one that could give me a definitive answer?

    I had a thought about adding some eteric oils like lavender or red cedar to the lanolin treatment but then that would evaporate fairly quickly and the problem would be back and bigger than ever?

    Thank you


    • Good question. I don’t really know about the lanolin, but I reckon if you suspended some good old fashioned mothballs in there (naphthalene flakes) then that’d keep the moths away even if they did like the lanolin. Naphthalene is one of those products that our great-grandparents used, and is still as effective today as they still work.

  140. Hello. Hope you’re able to help me.
    If I am using straight 100 p/c Sulphamic Acid on a shower screen that has built up Calcium but no soap scum, what dilution of Sulphamic Acid and Water should I use. Also if I paste or spray it on how long shall I leave it before washing it off.

    Looking forward to your advise. .

    • It only needs to be dilute. A 2-5% solution is plenty. Spray it on and it should dissolve the calcium (carbonate) pretty much instantly

  141. HI Dr Chemical,

    What chemical should I use to remove hardened pigeon poop from my back cement porch. There is quite a lot of it . The excess I have scraped off but find it hard work to scrub the remaining off with just water and a hardened broom.
    Thanks mate. Appreciate your work.

    Cheers Vee

  142. Hi Doc! Can you tell me what to use to degrease the rims of my car wheels? I have just used the last of a Karcher Car & Bike degreaser on my car rims and was wondering if there is an alternative to this.

  143. Hello Dr Chemical, I have been painting with oil paint and washed my brushes in oil. Accidently I knocked it over on the carpet. Have you any ideas on what to do please.

    • Hmm, that’s tricky. You need an alkaline degreaser – there’s a brand called Kenco that you can buy from Bunnings that is pretty good. Spray it on the carpet (I wouldn’t use it neat to start off- try several dilutions first) and then a powdered cleaner on it (like Vanish). You might need to do it a few times, but it should work.

  144. Hello Dr Chemical,Dr I have a problem with rising damp as well as a little flooding in my garage when it rains in which case the cause can not be rectified..but I was thinking that I could cove the floor to wall junctions as well as splurge a cementous slurry out and up from the junction but I want to mix up a inexpensive waterproof concrete of a crystalline function..i have since been raking my brain it doesn’t have to have structural strength it just needs to work have you any ideas of how or what would I use to block the pours in the concrete when or as the concrete becomes saturated with water..pls help me doctor..yours truly James.

    • I’d be contacting a tradesman if I were you – you need to fix the water leak. Any amount of cementing will only make the water pool somewhere else. There is premix quick drying cement that you can buy, and it’s cheap, but it won’t be a long term fix

  145. Hi there I am thrilled to find your website! I hope you found a publisher, by public demand; I would certainly put in a pre-order.
    Quick questions please
    1) Gel nails hardened with LED lights (not UV) – I am trying to decide on a brand and searches bring up numerous complaints about thinning nails after long term use of these products. Could the chemicals be responsible for damaging nail beds (or just the acetone or method used to remove?) Here’s the list of the primer: Isopropyl Alcohol, Ethyl Acetate, Isobutyl Acetate
    Polyurethane Acrylate Oligomer, 2-Hydroxyethyl Methacrylate, Hydroxypropyl Methacrylate, Isobornyl Methacrylate, Hydroxycyclohexyl Phenyl Ketone, D&C Violet #2 (CI60725)
    2) These companies all provide their own branded removers (basically acetone), my question is – do all the other additives even penetrate or do any good?
    3) Sandstone swimming pool tiles with salt chlorinated pool – started to degrade in some areas after 4 months from new(should have been advised better!). We sealed with water based stone sealant for very porous materials but water doesn’t bead everywhere anymore. Should we repeat or use something more “film like?”. Tiler said we would need to repeat every 2 years. (sorry I don’t have product name – from Bunnings)
    4) Same tiles with rust stains – used HCl with great effect (thanks Dr Chemical!) but Dear Husband had preceded that with WD-40 which remains. Help!

    • Re the nail polish, those chemicals are all pretty harmless, as is the acetone. It wouldn’t be thinning your nails. Can’t help with the sandstone tiles other than to say that sandstone is pretty soft and will wear away with time. I’d get the WD40 off with something alkaline – Easy Off oven cleaner followed by high pressure water should do it.

  146. accidentally i spill small amount of harpic desktop on a car. i thought that nothing happens. but now i say whithe drops like dust on that, i cant be near of the car beause the owner can discover that i did it. i dont know if the automotive paint is damaged.

    • If you’re talking about Harpic toilet cleaner, it won’t damage the paint on a car. It’s a mixture of dry acids and bases with some powdered bleach. It should just wash off, or at the very least polish off

  147. Can you please tell me how to get sticky tap off my paint wooden front door – I used sticky tape to hang Christmas decorations up and now I cant get the marks off from the sticky tape … please help !!!

    • Easy. get some washing soda from the supermarket (you might need to ask a staff member to find it), sprinkle in a couple of tablespoons, fill it with water. Bring to heat, let it cool, then tip it out, give a quick wipe and it’ll be clean as a whistle.

  148. Hello Dr Chemical,

    I have a slate floor which I’d like to reseal but I don’t know if the current sealant is water or solvent based. I was told to use methylated spirits. If it comes off it is water based. If it doesn’t it’s solvent based. Is this correct? Or is there another way of telling? Thank you in anticipation.

    • No, metho won’t remove a water-based sealant. But if it’s solvent-based, then xylene (paint thinners) should remove it, whereas it won’t remove a water based product. Water based sealants are very advanced these days and are now actually harder to remove than solvent based products

  149. Hi dr chemical,I have just installed a glass pool fence most people advise to coat with a product called enduro shield which puts some sort of barrier/ coating on the glass to protect and minimise cleaning this stuff is around 140 dollars for 500 ml surely there is a more economical way to protect the glass can you help please

    • There sure is. Use an automotive polish (Kitten #1) on a regular basis – or Mr Sheen, but the automotive polish will leave a thicker coating

  150. Hi could you please give me some advice on how to clean the resin top rail of a salt water above ground pool its starting to go a powdery look. thanks

  151. May you please advise how to remove red wine stains from glossy white floor tiles. Some wine had been spilt in a sheltered spot and was there for some time before it was noticed. I imagine it has had the opportunity to penetrate through whatever coating is on the tiles. This is a newly tiled floor. Thank you for your help.

    • Any oxidising product will do it. Look for any product with “Oxy-Action” in it – Preen oxy-action is probably the best

    • It’s in every supermarket I’ve looked in, but things are sometimes hard to find. I sometimes have to ask staff to find things

  152. Also to go with the Vicks question he put some on one of our roller blind which is made of a block out material what can we use on that as they can’t be taken down to be washed????

  153. Hi!!!! My son has put Vicks vapor rub on our painted walls!!!! I have washed it with water and detergent but the marks are still there!! I had a brain wave of using preen ultra degreaser on it but s bit worried that that too will leave a stain!!!!! Can you help?????!!!!! Thanks in advance!!!!

  154. Hi Dr. Chemical,

    I’ve read your post about weed killers. I’ve got some tough running grass in my veggie garden that is proving difficult to eliminate.
    I am thinking about mixing up some hydrochloric acid to use as a weed killer.
    What does hydrochloric acid break down into after it reacts with the weeds? And, are there potential soil health effects from the chemical byproducts (if any)?


    • That’s not a bad approach. There are natural compounds in the soil that will break down the hydrochloric acid after it’s done its job, and in any case it’s volatile, so it’ll evaporate

  155. Hi Dr Chemical,

    I am hoping you can help me. My 11 year old son found a tube of silicone while at my grandmother’s house and in a state of “boredom” decided to squirt it all over her colour bond fence and down the side of her house onto the bricks. My question is what is the easiest way to remove the silicone without stripping the paint from the colorbond fence and damaging the brick work. Thank you.

    • Get onto it with a heat gun. The bricks won’t be damaged and the colorbond won’t if you’re careful. Colorbond is very resiliant, but don’t blast it close – hold the heat gun a foot or so away and that should be enough to remove the silicone. But test the heat gun on an inconspicuous part of the fence first – I’m pretty sure it won’t damage it but best to check

  156. Dear Dr. Chemical,

    Is there any way to remove scratches from a glass table top?

    Thank you for your help.


    Beverly Miller

    • Best way is to fill them in. Get a silicone based automotive cleaner (Kitten #1) and rub it in. If you do it right the silicone will fill them up and they’ll all but disappear.

  157. Hello,
    We have accidentally got leaf curl fungicide (copper based product) all over the lawn through a contaminated watering can. The lawn is now half dead with a combination of blue, brown and yellow. It was previously pristine and lush :(

    How can we neutralize the copper in the soil/lawn? I’ve read it is very insoluble and can hang around in the soil for years. Otherwise I have read about adding some lime? I thought about adding top soil too. What do you think? Hope you can help!


    • Most copper compounds are pretty soluble. It’ll all wash into the soil with enough water. Don’t add lime – that’ll just make copper hydroxide which is insoluble

  158. Dr. Chemical whilst mowing my lawn I have put tyre scuff marks along the bottom of a colour bond fence can you tell me please how I can remove the scuff marks from along the bottom of the fence? Regards. Wayne King

    • Ajax powder cleanser would probably do it. Or a cheaper option would be washing soda (from the bottom shelf of the cleaning aisle in the supermarket)

  159. HI Dr Chemical,

    What is the best car wash to use that gets the dirt off my car – I want to use it in conjunction with a pressure washer, so as to avoid having to wash the dirt off by rubbing. I want to get the dirt off chemically.

  160. Hi Dr Chemical,
    I’m looking for a way to remove:
    1. The scale from newly-grouted tiles. I’ve tried watered-down vinegar in a spray bottle and paper towel.
    2. Spray paint graffiti from street signs. The signs are made from aluminium, covered in vinyl. The vinyl is usually white and printed directly on with a special printer in green text. I can send you a sample.

    • Hydrochloric acid 1 part in 20 (or 10) for the grout. For the paint, get a product called Citristrip from Masters and follow instructions on pack (there are also some YouTube vids as well)

  161. If I remove weeds from my driveway (rust coloured bricks) and using hydrochloric acid and salt – will this discolour the bricks either in the short term or the long term?

    • Not in the concentrations I’ve recommended. Concentrated HCl can fade red bricks sometimes, but dilute acid is fine (1 cup per 5L)

  162. I have a friend who has borestains on driveway.
    I have a 2000psi pressure cleaner & I’m an x farmer, so have used thousands of litres of chem.
    Please let me know the formula so I can clean my friends driveway as a xmas present
    Kind Regards, Kim

    • Either bicarb soda, washing soda or any powdered carpet cleaner will work well. Sprinkle in and leave overnight.

      If you don’t have any of these handy, hang them outside in the air for a while. It may take a few days, but they will eventually deodorise. There is no substitute for lots of air when it comes to deodorising.

  163. If I use the hydrochloric acid/salt/water as a weed killer do I have to be careful on what surfaces hydrochloric acid comes in contact with. Mainly I have a Large Above Ground Vinyl Pool and a Power Coated Steel Fence and Aluminium window frames. Also I have a couple of rabbits that have free range of the backyard during the day and is it OK to leave the rabbits out after spraying.

    • No, they are all OK with the acid in the concentrations I have described. It won’t damage any of those things. One thing that the film clip didn’t show was the dog running around on the ground after I had sprayed the acid. In those concentrations it’s completely harmless

  164. Hello Dr Chemical

    I had a written note on my oak, bedside table which unfortunately became wet and now the wood is stained with ink.

    I would appreciate some advice on how to remove the stain.

    Thank you!

    • The easiest way is to just reverse the process. Get a tissue and soak it in water with a bit of dishwshing detergent in it. Then just put it on top of the stain and leave it. Make sure you fold the tissue up so that it’s the same size as the stain it’s sitting on – otherwise it might cause it to spread

  165. Hi Doc,
    Please forward some wisdom, having a problem with cooch grass it has overrun and invaded a garden bed. Do you have a solution that I spray on the cooch with out killing the other plants. The other plants are well established. Please help, I’m hoping for a easy way than the old way of pulling them out because it’s near impossible to get the roots out and they just keep coming back.

    Regards – Will

    • Hmm – tricky. I’d try salt. Dissolve some pool salt in a garden sprayer (1 cup per 5L) and spray the grass. You should see an effect in a couple of days, without hurting the well-established plants. If that doesn’t work, add a bit of hydrochloric acid – half a cup per 5L. Since you’ll be spraying on the grass and not on the leaves of the plants, the only danger to the plants is the acid leaching into the soil, but the soil has things that will neutralise it naturally anyway

  166. Hello Dr Chemical
    I’m in BIG trouble – have just finished painting Wattle Decking Paint (water based) on all my decking and have now realised I’ve got heaps of it on the white gloss window and door frames – cant believe I was sooo slack as not to see it before I’d finished – didn’t wear my glasses and its been a good many years since I’ve done any painting!!! How can I remove it without damaging the white gloss on the window frames?

    • Hmm. Tricky. There’s no easy solution, but there’s something that might work. Go to Masters and get a product called Citristrip. It’s a very powerful paint stripper so you must be careful how you do it. If you follow the instructions, which tell you to paint it on and wait half an hour, it’ll strip ALL the paint off, which is not what you want.

      So here’s what I’d do – wrap a rag around your hand, then dip your finger in the Citristrip and rub it on the paint that you want to remove. With a bit of luck you’ll see the paving paint come off on the rag, and then you simply stop as soon as the paving paint come off, and before you start taking the window painting off. And then make sure you wipe it all off.

  167. Hi Dr Chemical,

    I was wondering if you could provide us with some advice on a stain that we have on our speckled white “essa” stone bench top. Not totally sure what caused the stain but it is light brown and doesn’t seem to want to be removed. We have tried metho and spray and wipe with little success. Please help


    • Without knowing what it is (and I understand that you don’t know yourself), we’ll have to take a broad approach.
      Firstly, spray an oven cleaner onto it. Many dyes are pH dependent (like the anthracyanin dyes in blackberries and blueberries) and sometimes if you just change the pH they go away. Next step is to try an oxidiser. Spray it with Preen Oxy Action prewash. Leave it for an hour or so, and hopefully the oxidisers will have done their job. If that doesn’t work, we’ll try enzymes. Tip some Biozet Attack liquid onto it, rub it in then leave it for half an hour. If it’s a food stain of some sort, this should shift it. Finally, get some Vanish Napisan, make it up as a paste with hot water, then rub it into the stain with a stiff sponge or scourer. Then let it dry. Hopefully the combination of enzymes and oxidisers will have done the job, but if they haven’t, then as a last resort, maybe the stain will wick up into the powder as it dries

  168. Hi Dr Chemical,
    We used sunscreen, let it dry on us, then wore white business poly cotton business shirts. The shirts went in the wash in Wollongong water with Biozet at 40 degrees. When they came out of the wash they have bright yellow stains all over them, apparently the sunscreen contains avobenzone with reacts with any iron in the water and leaves these stains after washing. I’ve tried Bam trigger, Bam oven, turned it orange, Bar Keepers friend (oxalic acid), bicarb, Preen stain lift and they won’t budge, any ideas how I could get these stains out? Thanks

    • Yikes – what a handful! So far you’ve tried enzymes, several acids, and a base. Not sure which Preen you used though.

      Anyhow, I’d try a solvent – acetone. Put some in a glass, dip one of the stained areas in, and just keep dipping it in and out. Alternatively, get some Vanish Napisan and make some up as a paste in hot water and rub it in. If it is iron, I’m a bit surprised that the oxalic didn’t work. Did you use it as a paste? Why is it called bar keepers friend? Next thing to try is citric acid (from cooking aisle in supermarket) used as a paste. If they don’t work, get some hydrochloric acid, dilute it 1 part in 10 and dip the stained bit in. If it is iron, that’ll certainly strip it out, and won’t damage the fabric

      • Hi and thanks for the reply – yes have a bit of a chemical lab happening in my laundry at the moment.
        I used the Preen pink trigger and it didn’t budge it. I had actually already tried the acetone and Napisan, had thought of them already just forgot to add to my above list – they didn’t budge it and the Napisan also turned it a more orange colour. Bar Keepers friend is an American cleaning product which is actually oxic acid, you can buy it online in Australia – it’s pretty darn useful around the house, and yep made a paste of it and no joy. But since posting yep tried the cutic acid and it has certainly lightened it along with some 48hrs hanging on the line in the sun……we are about to wear another 5 brand spanking new shirts this weekend and will be wearing the sunscreen, so I’ll attack any stains straight up with the citric acid – if not look like I’ll be trying the hydrochloric acid. Any idea why the stains would be occurring? Do you think it would be the avobenzone and iron reaction? If you Google avobenzone stain you’ll find I am with hundreds of people that has this problem. There is a market out there for someone who can invent something that get this stuff out, uvb sunscreen, great on skin, terrible on clothes!

        • The plot thickens. The citric acid suggestion was predicated on iron being the principal problem, as the iron-citrate complex is very strong (stronger than iron-oxalate I think). If the sunshine helps, I guess it’d be due to UV oxidation of the avobenzene substrate. That being the case, dousing the stains in a UV light (you can probably get them online) might be worth a try.

          As far as the HCl is concerned, it’s a question of how strong the solution can be without damaging the fabric. Poly cotton is pretty resilient, so you can probably get away with it. But the good thing about the HCl is that it’ll pretty much work instantly – whatever effect you see after 30 seconds is as good as it’s going to get.

          But there is one final chemical solution – chlorinated solvents. These used to be used by dry cleaners, which is why it worked so well, but they’ve now changed to much less effective solvents as the chlorinated solvents are potential environmental contaminants. The only product on the market that I know of that still uses them is a product in the paint aisle at Masters. I forget what it’s called, but it’s sold as a product for restoring gummed up paintbrushes. Look on the ingredients, and you’re looking for a chemical with “chloro”in it somewhere (eg dichloromethane).

          And one final suggestion while you’re at Masters. Get a product called citristrip – it contains N-methyl-2-pyrroliodone which is a potent paint stripper (but harmless to humans). Use it as a spot cleaner. Rub into stain, then soak stain for half an hour then rinse. And one more thing – automotive paint strippers are even more potent than citristrip (I’m told). Go to an automotive paint place and get their most potent stripper (something that’ll get two-pack paint off)

          Also, have you tried a steam cleaner (one of those ones with a jet nozzle). Bit of a long shot, but it’s worth a try

  169. Trying to detect chemical smell from plasterboard ceiling recently painted with British Paints Acrylic ceiling white (3 coats). Childrens stickers were removed and some places the original protective coating on the plasterboard was removed. How to we get rid of the smell from a residential bedroom? Do we paint it with a sealant and then paint with ceiling white and hope that will mask the smell. At the moment the bedroom is empty as the smell is so bad.

    • Only way is lots of air. The smell is from volatile molecules that have escaped the plasterboard and are hitting you in the nose. Leave an open window and they’ll escape from the room and not wind up back in the plasterboard. After a few days good airing you’ll find the smell will have diminished markedly

    • The black stuff is just the oxide that forms on silver. It can be removed by placing the forks in an aluminium tray with water and salt. Check this link. They use baking soda but table salt will work better.

  170. Hi Mark

    Nice website.
    I have a red clay paver driveway with some faint oils stones in 10 or so places.
    Can I remove the stains with degreaser or other?


    • Go into Bunnings and get a Kenco brand degreaser from the paint chemicals section. Use it neat. Tip it on, rub it in, leave it for 10 min then hose off. A steam cleaner will help if you have one.

  171. Hi,my partner washed his gloves(his a tree worker) in the washing machine with hot water and they were covered in fig sap now the sap is stuck to the base of the machine. What would you suggest to use to clean this?

    • Washing soda used as a powder cleaner will probably work (use as a paste with a scourer). If that doesn’t work, try acetone. Last resort is turps, but there will be a residual smell

  172. Hi Dr Chemical,

    The sunscreen I have been applying for my outdoor activities has attached itself to my car interior and I can’t seem to get it off with a microfibre cloth. It is that natural zinc oxide stuff called Invisible Zinc. What can I use to get it off?

    Also, I remember you said you were going to be releasing a book sometime. Is it out yet?

    Thanks for your help!

    • No book yet – still working on the publishing side of things.

      Re the sunscreen, I need some more details. By car interior I presume you mean seats. What sort of seats are they? Also, what does it look like (the stain)? General approach would be to use an acidic hard surface (or bathroom) cleaner (anything where the word “acid” appears on the active ingredients somewhere). If that doesn’t work, try an alkaline cleaner – Easy Off oven cleaner is a good one. Spray it on, wait ten minutes, then swab clean. If they don’t work, let me know and we’ll try other things

    • Very difficult, mainly because suede is probably the single most surface to clean in existence. I’d use steam. If you don’t have one yet, get a Steam Dream, or some other steam cleaner with a jet nozzle on it. Use the steam pressure to dislodge the vomit, and hopefully there won’t be much left behind. The good thing about steam is that there is minimal water, so there’ll be minimal water stains afterwards

  173. G’day Dr
    I heard you on the radio some time ago refering to a hand sanitizer that you had made but could not remember the recipe, would you mind sending it me.


  174. hi doc what takes out on the carpet dropped some inside of a Lilly don’t know what it’s called its stained it a bit yellow and what takes out body oil got some inside my bathroom wooden doors thankyou

    • I’m not sure I understand your question but if you have a carpet stain a good general purpose approach is the Vanish powder. If you can tell me more details as to what it is I could advise you further. Also, I’m not sure what you mean by body oil, but Turps is a good general approach

  175. Hi Doc – the bottom of our wrought iron front door has left some rust stains on the limestone tiles. To avoid cutting the tiles out what can we use to reduce/eliminate the rust stain? I have seen various comments about hydrochloric or oxalic acid.

    Many thanks in advance.

    • Yes, both of those will work. Get some hydrochloric, dilute it 1:1, put it in a generic spray bottle and squirt it on the stain. It’ll turn yellow and disappear before your eyes. Then just rinse it off with water. But it may take a couple of applications. Make sure you empty the spray bottle afterwards or the acid will destroy the mechanism

  176. I have a robotic vacuum (Neato) that has a problem with hair getting wrapped around a motor shaft that is inaccessible without disassembling the whole vacuum and spending lots of time cutting and scraping the hair away. Is there any chemical or product that will dissolve or soften the hair without damaging the motor and its rubber drive belt?

    • Short answer is no. Hair is an extremely chemically resilient material that will only dissolve in hot concentrated nitric acid, which of course you don’t want to use on your vacuum cleaner. This is one of those rare problems that chemicals can’t solve….

  177. Hi Dr Chemical,
    Would really appreciate any suggestions to remove yellow antiperspirant stains on a synthetic sun-smart shirt. The material is starting to harden. A great website.
    Tricia Brown.

    • Hit it with an oxidising prewash – any of them will work (eg Preen Oxy-Action). Spray on and let it soak for a while. Alternatively you could try an acid-based bathroom cleaner such as Easy Off Bam Soap Scum and Shine. I reckon the sulfamic acid will break up the aluminium complex that is causing the stain

  178. There were some stain marks on a stainless steel rangehood. I used a hard scrubber to remove them but this has left very obvious scratch marks on the stainless steel. is there anything I can do get rid of the scratches on stainless steel.


    • Go to an automotive shop and get some Kitten #3 Cutting Compound. It’s in a black tin. It’s the best SS polisher on the market

    • Depends what it is. If it’s table salt it will just hose off. But if it doesn’t it
      s probably calcium carbonate, in which case use an acidic bathroom cleaner. Easy Off soap scum and shine contains sulphamic acid which will do the job

  179. While trying to remove areas silicone glue left on our brand new windows by the window company we used lacquer thinner and wiped it around on the windows which left big smears & streaks when the sun shines in. How do we remove this? Tried Windex, vinegar with soap and water and nothing helps. Thanks.

  180. Hi Dr Chemical,

    What’s the best way to clean an exhaust fan that’s above a stove? I put it in the dishwasher and its still not clean. Its got lots of grease on it.

    • Easy. Spray it with some Easy Off oven cleaner, let it sit for half an hour, then put it through the dishwasher again.

  181. Hi Dr Chemical,
    How do you remove the smell of Dog Pee from a rug/floor mat? It is a multi coloured synthetic rug with a long pile, the stain I am not worried about, just the awful odour from the urine. I hope you can help.
    Thank you in advance

    • Put some vinegar in a spray bottle and spray it lightly over the effected area. If you have a steam cleaner you could then try that. Finally, sprinkle either bicarb soda or a laundry powder on it and leave it for a couple of days before vacuuming up

      • Thank you for your reply, unfortunately we have sent the rug off to be commercially cleaned. As we need the rug in situ asap in a commercial setting.

  182. I like to swim at our local swimming pool, but the smell of chlorine left in my hair, even after washing it, remains. How can I remove chlorine from my hair ?

    Also, when washing my clothes, in cold water, with Dynamo detergent on the clothes, and canestan rinse and fabric softener in the centre rinse dispenser, it will often leave dirt marks on my dark clothes – it looks like dirt or undissolved detergent and if I rub the fabric together some of it seems to come off. Do I need to clean my washing machine, and if so, how do I do that ? I always empty the lint catcher at the bottom of the centre rinse dispenser.
    Thank you.

    • Regarding the chlorine smell in your hair, it’s not actually chlorine, in just the same way that the “chlorine” smell at the pool is not chlorine – it’s chloramines. In other words, it’s the product of the chlorination process, not the chlorine (hypochlorite) itself.

      So in your hair, the hypochlorite has attached itself to amines in the protein chains that your hair is made up from (protein is made from amino acids). Your best chance of reversing the process is to acidify your hair. You could use vinegar (acetic acid) for this – if you don’t mind your hair smelling of vinegar, or perhaps dry pool acid (sodium bisulfate). Alternatively you could try using Seba-Med or some other pH-controlled shampoo (but pH 5.5 is only mildly acidic and may not be acidic enough to do the job).

      Regarding your washing machine, the problem is that you are using the wrong shampoo for cold water. The Dynamo contains components that need hot water to dissolve – when you use cold, undissolved residues are exactly what you see. If you are absolutely stuck with cold water, switch to a specialist cold water detergent (such as Cold Power). Much better, however, is to switch to either warm water with a biological (enzyme-based) cleaner, or hot water (with your Dynamo or OMO) if you can.

      In any case, a load of hot water should clear the residue out (a bit of vinegar tossed in may help a bit)

  183. Hi Dr Chemical,
    I’ve noticed that people have asked about mechanics grease on clothing, but what should I do about removing it from cream carpet, which is a wool blend I think. Should we just replace it?
    Thanks for all your great tips.
    If you still haven’t found a publisher, why don’t you do it yourself? I met a bloke at billabong roadhouse and that’s what he did, he said it cost him about $2000 for the first run.

    • It’s not too difficult. Go to a hardware store and get the Diggers degreaser. It’s in a 1L black bottle and is an alkaline salt-based product that works very well.

      All you do then is use it on a paper towel (changed regularly) to blot up the grease.

      And yes – I am pursuing the self-publishing option. Today Tonight are going to do a story on it when it’s published, so publicity shouldn’t be an option

  184. We have a flat granite headstone in the cemetery that the coons or something likes to poop on and I have tried everything to get them to stop. What do you suggest? I have bought all kinds of stuff from a pet store, and also clorox, and peroxide. Please help as it stains and I have to go almost every day to get rid of it and try something to keep them away. Thank YOu

    • Hmm that’s tricky. You want something that produces a smell that deters them? It might be worth trying ammonia. Get some ammonia from the hardware store, fill four glasses with it, and place one on each corner. Hopefully they’ll get a whiff from one of them and it will drive them away. The other advantage of this is that ammoniacal compounds are in urine, so it may smell to them that something else has urinated there and it will frighten them away.
      To protect the headstone from the poop, polish it with a silicone car wax – this will provide a protective coating that will stop the poop seeping into the granite

  185. Hi Dr Chemical

    Can you please give us some ideas to clean a red wine spill from carpet. The carpet is 100% Solution Dyed Nylon and is a dark grey colour.


    • Easy. Hit it with an oxidiser (something with “oxy-action” written on it somewhere). Preen Oxy Action will do the job. Squirt it on, leave it for 10 min, then swab it up

  186. Hi Dr Chemical,
    we have a Bore and the lime in the water has pockmarked the glass pool fence is there a way A to restore this and B protect the glass from the retic onslaught of summer?
    cheers and I love your work

    • Squirt it with a product containing either sulfamic or citric acid (BAM Easy Off or look for tile and bathroom cleaners in Bunnings or Masters). Look in the fine print on the label to see what the active ingredient is. If it’s lime (calcium carbonate) you’ll see it bubble and fizz when you spray it on. Then protect it from future attack with a silicone coating (either Mr Sheen or Kitten #1 polish). Or if you like I can come and quote you on doing it for you. 0414 759565

    • For rust get some hydrochloric acid and dilute it 1:1, then just tip it on. For the gum leaf stains sprinkle some caustic soda flakes on it, wet it down and rub in with a stiff brush. Leave for 10 min and then hose off

  187. Hi Dr Chemical.

    I have recently used artline permanent markers on paper for my art coursework. The ink has dried, but the strong smell of the marker is still there. Will it go away by itself or is there another way to get rid of it? It is really distracting and smelly. Please help! Thank you so much.

    • Yeah it’ll dissipate soon. They use esters as the solvents in those things these days, because they smell more pleasant than xylene. That’s why most of them will advertise “contains no xylene” on the side. There was nothing wrong with xylene – it just had more of an industrial smell than the sweeter smelling esters.

  188. Hi Dr C, I have two teenage sons that have been racing go karts for many years and their race suits are a nightmare to clean. Basically they end up with grease and fuel stains on them. I have tried many laundry cleaning products with limited success and find the best treatment is spraying them with a kitchen cleaner like Mr Muscles or Spray and Wipe first before washing – the downside is they retain the smell of the cleaning product even after washing. Then I read your column in this Saturday’s West Australian Habitat about oven cleaner as a pre wash for removing cooking oil and wondered if this is likely to work on greasy race suits without damaging the suits? Any ideas appreciated, especially as the suits are predominately white in colour. Thanks!

    • This is pretty straightforward actually. Oven cleaner won’t work as it only works on animal or vegetable fats. What will work, however, is a degreaser. There are two types of degreaser – the older solvent-based types, and the newer products that are based on alkaline salts, and these are the ones that you want. Go into Bunnings and buy a Diggers brand product that comes in a 1 litre bottle. Put some in a generic squirt bottle (it’s a black liquid) then squirt it on the stains, wait a few minutes and then wash. And if you aren’t already doing so, use a hot wash.
      When I did a review of prewashes on Today Tonight a while ago, this product was the overall best performer – better than the laundry products, and it is particularly good on oils

  189. Hi Dr Chemical
    I managed to get a couple of drops of unleaded petrol on my clothes the other day… I thought the smell would come out straight away because I washed them both as soon as I got home & they’ve been dried on the washing line… but no, the smell is still there. I’m not sure if there is a stain too, because the clothing items are both black.
    Please can you recommend a product or tactic?
    Many Thanks

    ps: I find your opinion on the vinegar & bicarb issue interesting – I did try it once & got no result for my effort – plus I was left with a white powdery residue that I had to keep wiping & wiping to finally get rid of… pppfffttttt!

    • The best way to remove the petrol smell is with either an automotive degreaser (Bunnings sell a Digger brand product that works well) used as a prewash (with a hot wash) or a steam cleaner. And the best way to get set bicarb off a surface is with more acid. Vinegar will do it but you could also use BAM Easy Off which is stronger.

  190. Dear Dr Chemical,

    Thankyou for the reply RE: mould inbetween the tiles in the grout. I have not tried the water and vineger yet, as I do not have a steam cleaner and I do not want to hire one for such a small job. Would just a good scrub do? Also I forgot to mention that the mould seems to be aqtually IN the grout itself and not just on top, so, I don’t think it will just “flake off.” In the past I have tried bleach and another time I tried jiff. The bleach just “bleached” the mould and the jiff just took off the top layer (with alot of hard scrubbing) so this is what makes me think the mould has GROWN in to the grout. I have thought of having it taken out and replaced, but I am sure that would be an expensive job to have done. ALSO, I mentioned my electric oven. What do you suggest I could use to clean the build up of grease that has been baked on. Looking forward to your reply. Thanking you in advance.

    • A good steam cleaner will cost you about $200 and is an excellent investment with many uses around the house. But to get ingrained mould out you’ll have to actually dissolve the grout. You want either phosphoric acid or hydrochloric acid. Ajax Professional Bathroom Cleaner (purple bottle) uses phosphoric, or you can get some hydrochloric from the hardware store. Dilute it 1 part in 5, put it in a generic sprayer, and that’ll dissole the upper layer of grout along with the mould. For you oven, use good old Easy Off caustic oven cleaner. Or get in there with some washing soda and a scourer – either will work

  191. Dr Chemical,please help,we have a house with a substantial amount of the flooring being polished aggregate concrete ,so it has a nice “terrazzo” look,problem being its a nightmare to clean,i have used oven cleaner as per your site ,tried a steam mop (pointless) and even hired a heavy duty roller cleaner sort of worked but really seemed to move dirty water around !


    • Not sure exactly what you have on it, but ammonia, 1 part in 20, will clean most floors. Mop it on, then mop it up and let it dry

  192. Hi I was reading the your 6 power products in The West Australian – Habita section in particular No.5 OzKleen Shower Power. However on your website under the section of Chemistry in the Bathroom it appears it states, “Soap scum and bathroom scale are both alkaline, and so a shower cleaner has to be acidic, and for this reason, the BAM trigger is by far and away the best shower cleaner on the market.”

    I was just curious which one is better?

    • Excellent question! They both work – the BAM uses sulfamic acid and the SP uses citric acid. The BAM is the stronger product, but it has a poor trigger mechanism which means you have to spray it a lot to get coverage. So you could get the SP, and when it’s used up, buy the BAM and use it as a refill for the SP, which has a much better trigger

  193. Just put new carpets down. The layer suggested to put napthalene flakes under the carpet.
    It turns out that the tenant seems to be allergic to the odour.
    Airing the place is not working. Neither is a series of bowls of white vinegar.

    PLEASE can you help ?

    • I’m afraid you have a problem. It has an incredibly strong smell, and can be detected at very low levels. Regardless of whether its actually naphthalene or the synthetic alternative (1,4-dichlorobenzene) that is now used in mothballs, you have a compound that has a high boiling point (150-170 degrees) and can therefore only be removed by superheated steam – these kind of temperatures are certainly beyond domestic steam cleaners which just boil the water. If such a thing were possible (and I don’t think it is) a dry cleaning process could get it out. This is where a solvent of some sort is used to dissolve the substance in question, and no water is involved. I’m not sure exactly what solvents dry cleaners use, but if such a process were possible for carpets that’d be what you want.
      In any case, it seems like idiotic advice to me, and I cannot see how you’d get the smell out other then to pull up the carpet (and throw it out) and clean it all up underneath. I’d be going back to the carpet layer and telling him the problems he’s caused, and then maybe going to the ministry of Fair Trading (now called Dept Commerce) if needs be.

  194. Hi there,
    This might sound kind of silly but here it goes.. I recently cleaned some leather items in a baking soda and water solution. Needless to say it ended up ruining my stuff, but my question i, was this a dangerous process? I did some research after the fact to see why the water fizzed a lot and why it took out the dye and found that leather contains lots of chemicals. Could these chemicals have leaked into the solution and hurt my skin when I was washing them?

    • I’m not sure why you chose to use baking soda to clean it – baking soda will clean almost nothing. Better to use Mr Sheen. As for leather containing lots of chemicals, the only ones that it contains that I am aware of are natural oils, and none of these are in any way toxic. The fizzing indicates the presence of an acid of some sort – you weren’t mixing it with vinegar (acetic acid were you)? Also, baking soda will not ruin the leather – it’s just not strong enough. Worst case scenario is that it’s discoloured it. Rewax it with some beeswax and possibly shoe polish to restore the colour

  195. What can I use to remove burnt popcorn & olive oil from the inside of a stainless steel saucepan. First I tried scrubbing with a stainless steel scourer, but that hasn’t completely removed the burnt marks. Next I tried a paste of water & bi-carb soda leaving overnight & then scrubbing in the morning. Lastly I have tried a paste of vinegar & bi-carb soda leaving overnight & scrubbing in the morning. Both haven’t shifted all of the burnt marks. Please help

    • I’m not sure why you mixed bicarb soda and vinegar together, as all they do is neutralise each other, and the have no cleaning properties whatsoever. Add a generous amount of washing soda (sodium carbonate), bring it to the boil, let it cool a little and then tip out. Anything that is left behind will be removed with a quick wipe of a kitchen scourer

  196. Could you please advise me on what to use to clean mould from the grout inbetween my tiles in the shower and mould from the ceiling?


    what to clean the inside of my electric oven with.

    thankyou so very much

    • Dissolve a few tablespoons of salt in litre or so of vinegar, then put it in a garden sprayer and spray on the mould. Leave overnight, and then come back with a good steam cleaner and the mould should just flake off.

  197. There is a green substance on the bottom of my ice cube tray. Does does not come off on the cubes, or upon washing. I have hard water–is it possibly lime build-up? Thank you, please advise.

    • Green? What colour is the tray itself? Lime is calcium hydroxide, which is white. If it’s a mineral buildup of some sort, vinegar will shift it, although you only get mineral buildups when you boil water, not freezing it. Send a photo to

    • Yes. Make a paste out of a laundry detergent and scrub it. The combination of the scouring effect of the powder and the cleaning action of the detergent will do the job for you

  198. we have been using a new sealcoat on our pavement but it seems to get sticky and track the hoter the day gets can you tell me why its doing that and how to stop it thanks

    • I’m afraid you can’t – it is either the wrong product for the job or a poor quality product. I’d remove it (high pressure water) and start again. I find the stuff sold in Bunnings comes with good advice generally. Talk to a paint expert and make sure you have the right product – this certainly should not be happening

  199. I have a broken 4×4 mailbox post with a concrete footing and a concrete sidewalk covering that. I’d like to remove the remaining part of the post that’s below ground and use the hole in the concrete to hold a new metal post. Is there a readily available acid like muriatic acid or battery acid that would dissolve the wood in a few days saving the tedious labor of chipping out the old wood below ground? Also, what would be best to neutralize the acid with.

    Thanks Dr. Chemical!

    • No I’m afraid that there is nothing that will actually dissolve it (short of hot nitric acid). But hydrochloric may embrittle it, and make it easier to get out if it was soaked for a while. If you’re worried about the acid getting into the soil and poisoning it, don’t be – there’s plenty of stuff in the soil that will neautralise it naturally. But otherwise, soda ash (washing soda) will neutralise it (from cleaning aisle in supermarket).

  200. hi Dr. Chemical

    I like your website i learned a lot from the posts. My problem is the double wall of our house. The carpenter used hardiflex as the double walling and i really hate it because the smell really causes me coughs. what will i do to let the odor out? will the bad smell disappear if i paint it? what kind of paint will i use?

    Thank you
    Best regards

    • The best remedy for the smell is lots of air. But painting it will work too, as it will seal it. Use water based paints – their formulas are very advanced and avoid the solvent smells of the older oil-based paints

  201. Diane on August 16, 2013 at 11:27 am said:
    Hi Dr Chemical
    I have just recently discovered you website and its already helped me with cleaning which I hate, but now I dont! well not so much…LOL! Can you tell me the best way to clean a large area of ceramic tile floors. I’ve moved to qld from the UK & aussie houses have massively large ceramic tiled floors that seem to never end. I vacuum and steam them but they take ages. do you have any better solutions to make it easier or . I’ve just used your kitchen counter top remedy Metholated spirit and water, which is great for mirrors and windows too, would this work on ceramic tiled floor with a mop or do you have other remedies. Thank you so much, Diane PS Any news on the new website (not blog) and book yet & how can i find it

    • Best homemade floor cleaner is ammonia, say 1 part in 50. It will strip off any wax or polish on there and also any skin fat (from bare feet). Just make some in a bucket, mop up and let it dry.

  202. Hello Dr Chemical,
    I have just learnt the hard way that you should not put aluminium foil on the base of an enamel oven. I now have no enamel on the base of my new oven and the alfoil is imbedded into the base. The base of the oven is not removable as it is an entire oven unit.
    How can I remove the alfoil?
    How can I fix the enamel?
    Thank you
    Kind regards

    • I’ll give you a couple of options. Aluminium will dissolve in either an acid a strongly alkaline solution. Get some BAM bathroom cleaner (with Sulphamic Acid – look on the ingredients) and spray it on and leave for half an hour, before wiping off. If that doesn’t work, get some caustic soda and sprinkle it in the oven. Wet it down with a minimum of water, and let it soak for half an hour. Wipe up with a scourer and glove (it has strong fumes but they aren’t toxic). Lastly, try the same thing with a 1 in 10 solution of hydrochloric acid (hardware store). Once again, strong fumes but not toxic

  203. my Jacuzzi uses a chemical named REDO KAT and REDO LYTE.
    What are these chemicals and which one is Alkaline please?

    • I’m unfamiliar with either of these and cannot find any information online. Who makes them? Alternatively, ask the purchaser for an MSDS and tell me what the ingredients are

  204. Hi , I have just whiled away a couple of hours reading your amazing solutions. I am actually looking for a way to remove a foggy film on a wall of mirrors. This is not always visible from all angles, but has been frustrating me for years. I usually use a windex type cleaner with paper towels or an old clean linen cloth. Is it a build up of some inferior product I have used? Would love to have a sparkling mirror wall again.

    • No, it’s not a build up – it’s just the surface chemistry.

      Get a dishwashing detergent and squirt it on the surface, then rub it in with a clean cotton rag. Initially of course it will smear, but just keep rubbing. After you have rubbed enough, the water will evaporate and it will clear. This will then leave a film of surfactant on the surface that will stop the water beading up (which is what causes mist). Use Morning Fresh, as it contains the most surfactant and least water

  205. my contractor over spilt some cement on our new driveway, the color and finish does not match the new driveway. the guy said it would wear off over time. we do not want to wait for ever if you know what i mean. so how can we remove the overage.

    • I need more details on this. If it’s white cement on white cement he may be right. But if some chemical treating is required, I may be able to help. Call me on 0414759565 and I can have a look at it

  206. A Tiki Torch was blown over and spilled some oil into the pool. How can I remove the oil from the surface of my pool?

  207. Hi, I would like advice on removing the sticky residue left after peeling off old window tinting film. I have thought of using eucalyptus oil, goo remover and/or a blade. Thanks in advance, Ari.

    • That’s a bit tricky. You need an acid, but you don’t want to dissolve the pants. I’d try BAM trigger (with sulphamic acid). Look on the ingredients on the pack to make sure you have the right product.

  208. Hi Dr chemical,

    I have a canvas seat cover which which has been subjected to the western australian outback, more specifically it has been covered in the red outback dust, it is proving to be extremely stubborn. Would you be able to advise what I can use to clean it. Any advise would be much appreciated.

    Kind regards


    • The red dust is ferric oxide. To dissolve it chemically you’d use hydrochloric acid, but you don’t want to do that as you’ll dissolve the canvas. It’s not adhering strongly to the surface, so hosing it or squirting it with a HP water cleaner is your best bet

  209. I want to use a product called ALG (alligare) super marker dye. The product is used to show where you have sprayed an herbicide. I wonder if that marker dye will permanently stain wood or concrete?


  210. I would like to ask which type of professional carpet cleaning is best when there is a crawling baby in the house. I am worried about chemical residues on which will be left on the skin and be on the toys.

    • There’s probably nothing to worry about. Professional carpet cleaners use mostly steam with biodegradable surfactants (detergents).

      But having said that, I don’t know what actual products they use. It’s worth asking them the question, and then if you get back to me I’ll do a little research.

  211. Hi Dr Chemical,

    You have recommended Dr Sheen to keep shower screens cleaner for longer. Just wondering if you’re referring to the original aerosol or the spray pack Mr sheen has (e.g. potpourri trigger pack).

    Thank you!

    • Aerosol only. The trigger pack is nowhere near as good as the aerosol. This is pretty common actually, as aerosols and trigger packs are always a different formula

  212. Hi Dr Chemical,

    I was diagnosed by an enviornmental allergist as being sensitive/allergic to formaldehyde (and dust). My symptoms are a blocked nose, inflammed/dry thoat, headache, and light headed. We had new carpet put in which even caused asthma type reactions which have now stopped, and the headaches and light head were only caused during testing. Even my daughters new bedroom suit is bothering me. I believe I will ultimately have to get rid of the new carpet/bed suite, but I would like to test formaldehyde levels in my body (I assume high levels). Do you know where I can get such testing, or if in fact such testing exists? (I’m in Melbourne metro). The testing is really to justify that I need to make some major changes to my home. Note that my daughter has similar symptoms, and it her that I am most worried about.


    • I’m afraid that the medical testing aspect is beyond my level of knowledge. But I’d get a second opinion on the diagnosis. Formaldehyde has now been phased out of most products as it is carcinogenic, and I’d be very surprised if there was enough in a carpet (if there was any at all) to be able to show up in a blood test. As to the reaction to the carpet, it more likely that it is plasticisers and binders that you can smell. Also, don’t assume that just because you are experiencing these symptoms you are being poisoned – there are many chemicals (like bleach) that cause these symptoms that are harmless

  213. Hi Dr Chemical, My dog has started urinating on my grand daughters small trampoline and the smell is horrendous even though I wash it down daily. I have tried vinegar, citronella but with no success. Can you recommend something that I may be able to use to rid the smell and stop him from doing it again?
    Thank you

    • I’d try ammonia. Make up a solution 1 part in 20 and spray it all over. It’s not harmful but may put your dog off. If it doesn’t work try 1 part in 10

  214. Hi Dr Chemical
    I used a tile cleaner that contained 70 per cent sodium hydroxide which has
    splashed onto an aluminium skirting has left white marks on
    skirting possibly etched into the metal.any ideas with what I can try to
    remove or restore alloy or is it,permanently damaged .i tried turps also
    autosol (polishing compound)did not work.
    I am desperate for any help please.
    Thank you for taking the time to read my mail

    • It’s pretty easy. Get some Kitten #2 cutting compound from an automotive accessories place (in a red tin) and use that as a cutting paste – that’ll get it off. It’s only on the surface

  215. Hi,
    I have a few questions I hope you can answer.
    1) Why are surfactants needed to remove a stain? What is their role in the process?
    2) What role do emulsifiers play in removing a stain?
    3) How would an organic stain like blood be removed?
    4) Would enzymes be used to remove organic stains?

    • Good questions!
      Firstly, the role of surfactants is explained here

      The word “emulsifier” is somewhat overused. Technically, emulsifiers and detergents are not the same thing, as they have different functions. If you look their HLBs however, you will see that detergents have about the same HLB as oil in water emulsifiers. This means that they are chemically interchangeable, but if you are going to wash dishes you use a detergent and if you are going to whack everything into an ultrasonic emulsifier you use an emulsifier. Physically, a true o/w emulsion, like milk, is opaque, as the emulsifier has broken the oil micelles down into droplets that scatter visible light.

      Without the mechanical action of an emulsifier, however, like when you’re washing dishes, the micelles are much bigger, and they don’t scatter light as much. So while dirty dishwater may be murky, it’s not white and opaque like a true emulsion.

      Blood is easily removed by ripping the iron atom out of the middle of the porphyrin ring. This is easily done with Citric Acid (used as a paste).

      Yes, enzymes are very good at removing organic stains, and this has been one of the most exciting advances in cleaning materials in the last decade. All the best laundry prewashes are now enzyme based, and Biozet Attack is a detergent that is highly enzyme-based and will remove most things. But if you’re using an enzyme-based product, the water must be warm, around body temperature, as enzymes are natural products that are designed to work at these temperatures only. Much colder and they just don’t work, and much hotter and they just fall apart!

  216. Can you tell me how to get neatsfoot oil off a ceramic tile floor? My husband spilled some and we wiped it up, but it is still sticky

    • Try Mr Sheen – the white spirit it contains should do it. Failing that, get some acetone from the hardware store.

  217. Hi, Just wondering how I can get out nail polish from clothing. A bottle dropped and went all over my new black work pants. The nail polish has now dried. It also went over my black fabric shoes. Hoping you are able to help.

    • Acetone will do it (from Bunnings). But do a colourfast test first on a inconspicuous part of the garment first, as it’s an aggressive solvent and may make the dye run

  218. I camped under pine trees and now have gum on my canvas. Is there a way of removing the sticky gum and not damage the canvas? Thanks

    • Canvas is cotton, which is good in this case, as you can use any solvent you want and it won’t damage it, although it may remove some of the dye. Orange Power Sticky Goo and Spot Remover (from Coles) should do it. Or, in order of increasing strength, white spirit or acetone (from Bunnings)

  219. Hi Dr Chemical. Many moons ago on 6PR you spoke of a cream that was made for another purpose and they then discovered this cream would erase scars. ..even old ones. I did write it down then lost the piece of paper.. Probably an age thing. I have a feeling the product started with a W.. but then again, not sure. I believe it was from Europe but was available at local pharmacies. Thank you … Vicki

  220. Hi Mark
    I have a huge problem , we have guests arriving today into a freshly painted room that now stinks badly of the paint odour.
    the paint used was a 5yr old wash and wear acrylic paint that had been stored in a garden shed
    It did not have that custard style skin over it hence the reason we used it
    How do we negate the smell Mark ?
    0435 383 705

    • Trial and error I’m afraid. Odour neutralisers from the supermarket have general household smells in mind. The idea is that the neutraliser targets the same receptors in your nose as the smells in question, and they can work remarkably well. I’d try odour neutralisers from an auto accessories store, as the smells in a car are closer to paint than general household smells

  221. Hi Dr Chemical, I have an area of approx. 40sqm of pavers , (under cover of a patio area) these pavers have been laid for several years, we started to seal them and notice salt coming through them so we stopped , we are now trying to take that seal off clean them and possible redo the seal again as im hoping that after all this time the salt will not appear ,, can u please advise me on what I can use, have tried vinegar in water, it works but far to big an area to do this. as its not taking the seal of completely and its only on half the area as well , would take months lol .Thanks for ur help .

    • What sort of sealer is it – water based or solvent based?

      General approach – try a heat gun. Pick a tile over in the corner and blast it. It may just peel off. If it burns and goes black just keep blasting it and it should flake off.

      Or try caustic soda. Get a 2kg tub from Bunnings, and sprinkle it liberally over a couple of tiles as a test. Wet with a minimum of water, leave it to soak for half an hour, and scrub with a stiff broom. It may then either hose off or come off with a HP water cleaner. To do the whole area you may need more than the 2kg.

        • OK, in that case try xylene (from hardware store). If that doesn’t work, Citristrip (from Masters) will do it, but it’s expensive.
          Or if you’re adventurous, try getting your hands on N-methyl pyrrolidone (or NMP) from a chemical supplier, but you might find it a bit hard to get in retail quantities

  222. BACKGROUND INFO: I have vigorously scrape a concrete floor after soaking it with adhesive remover in order to remove old adhesive used to glue down a hardwood floor over that concrete. The hardwood floor had water damage and grew mould. The concrete now is sealed with the residue glue left after from the scrape down with adhesive remover and is impervious to every liquid I have tried to apply to kill and remove the black mould that stubbornly remains as a 0.5mm top layer on the concrete. Even phosphoric acid won’t react with this concrete! Before I have professional concrete polishers grind off the remaining stains (and possible mould), I thought my last do it yourself approach would be to blast the area systematically with a heat gun to kill the mould before reapplying a new hardware floor.
    QUESTION: Do you think a heat gun would effectively kill all the mould remaining in the the residual glue “seal” and upper 0.5mm black mould layer of the concrete?

    • Yes a heat gun would probably work, but I’d try pool strength bleach first (12%). Pour it on, let it soak for half an hour.

  223. I have vinyl laid in our new home, which is textured.
    I was unable to clean it for the first 12 mths due to surgeries and now I would like to know what to use to get rid of ingrain dirt/grease that has built up during the time some-one else was just using a steam mop on it.
    I am unsure whether I need to scrub with something bristly or a chemical will dissolve/attract the dirt/grease particles. I have a great interest in chemistry/bio-chemistry and have a degree in Nutrition but it does not help with my floor. I done want to damage the vinyl it is only a few years old in a new house.
    I look forward to hearing your reply
    Kind regards

  224. Hi Dr Chemical,
    Jarrah decking originally oiled with Sikkens HLS Woodstained(007Pine) with super
    natural clear finish.Approx four years later deck needs to be resealed through exposure to elements. Through misunderstanding deck coated with Marine Special Timber Finish Wattle U400 2 Pack. Is there are method available to remove the latter without damage to the wood itself?

    • Not that I know. 2 packs form a highly resilient polymer which resists any attempt to remove it. I’d talk to a panel beater – 2 pack paints are common in the automotive industry and there may be a proprietary product that will do the job.

  225. Hi, I used some exit mold remover on my bathroom vanity to get rid of the mold, but obviously did not rinse it all away. It has now left a yellow stain on the vanity. Is there anything at all that may remove it, a paste that may absorb the stain???

    • Uh oh! If it’s a plastic vanity you may have damaged the plastic (oxidised it). Get some Kitten #2 Cutting Compound from an auto accessories store and try that – it’s a mild abrasive that may scrub it off without damaging the plastic

  226. Hello Dr Chemical
    I’m trying to get rid of white stains on painted concrete outdoors where pot plants have been draining. Have tried CLR, bleach, vinegar and scrubbing. The stain seems to have a hard finish which when scraped vigorously becomes powdery. Any input would be appreciated


    • Hmm – tricky. If it’s come out of a pot plant it could be any combination of soil or fertilizer chemicals. By the physical description it could be calcium sulphate (gypsum), in which case there is no magic cure for removing it as it is both insoluble and inert.

  227. Dear Mark,

    Long time no hear or see. Hope life is rocking for you!
    Mark I have made a mistook!!! I decided on the exterior walls of my white colourbond Donga to put strips of brown packaging tape. Now of course over several months it has set beautifully! I cannot scrap it off, nor degreaseors, paint stippers, petrol, or any other substance will work to remove the hardened brown plastic tape off the face of the white walls. Tea tree oil will work a little and it smudges a fantastic brown stain over the rest of the walls when rubbed vigoursly. You are my only hope OBI WAN MARKUS. Failing a chemical attack plan from you I will be removing a replacing the panels one by one!!!! Oh the pain and the cost!!!! Many tears!!!


    peter s.

    • Hi Peter, from you to hear is good (that’s my best Yoda impression). Acetone will do the job. It’s a very aggressive solvent, but it won’t damage colourbond (at least it shouldn’t – check an inconspicuous area first). And wear gloves when you use it, or it will strip the fats out of your skin. Alternatively, you say you’ve tried paint stripper? Was that xylene, because xylene should also work, but not as readily as acetone.

  228. Hi Dr Chemical,
    we have a strange sweet smell coming from our roof cavity and entering our bedrooms upstairs (how? through painted gyprock?), The smell it only evident when it is over 20 degrees. When it gets really hot – over 30C the smell takes on a burning odour.
    We first called a plumber thinking it was a blocked drain or sewer but they couldn’t find any problems.
    We have removed all our insulation thinking it was that but the smell still remains. The insulation was the recycled loose fill that may have been treated with boric acid – would the boric acid cause a sweet smell?.
    We have had the roof checked out for vermin, possums, birds etc- all good.
    We have taken the concrete tiles off the roof and heated them up on the stove to see if they were the cause of the smell – they weren’t.
    We did have a roof leak and have patched that. I know the damp smell that a leak will cause and it is quite different to that.
    We have tried an ozone generator in the roof and in the rooms but it only takes away the smell away for about 12hrs, then it comes back.
    There were some offcuts of gyprock lying around loose up in the roof cavity that we took down and they have this sickly sweet smell embedded in them. I am getting desperate, I do not want the expense of having to have to take down all the gyprock and replaster everything – do you know what the smell may be and how to fix it.

    • Hmm tricky. It sounds like it’s one of the chemicals used in the gyprock manufacture. If that’s the case it’ll take an eternity to dissipate. How long has it been there? I’d be going back to the gyprock manufacturer and taking it up with them. They should be able to identify it – either oops, that is faulty gyprock – we’ll pay to get it replaced, or no, it’s not us – it’s (…..). And then if they don’t play ball, take it to consumer affairs – it costs about $30 to make a claim against them I think.

      The fact that ozone removes it tells me that it is an oxidisable organic of some sort – perhaps a binder or something that they got wrong in that particular batch.

  229. Hi Dr Chemical,
    I’ll email a pic. We’ve been told by two people they are sap stains on our poured limestone pool surround and also on the bottom of the pool on the plaster. We’ve tried liquid bleach and powdered chlorine to no avail. We see these stains on the cement footpaths all around the neighborhood. Thanks so much.

  230. Dr chemical I install shower screens and and on request apply a glass sealer which they call it a nano coat which is quite expensive and wonder I wonder are windscreen sealers or sheen as you suggest would work and keep working or do you have any suggestions

    Regards nick

  231. where can I find a non ionic liquid detergent for mixing with white spirits to clean marble(and what brand)? Heritage house restoration advisors have recommended this.

    • Liquid laundry detergents are generally nonionic, and if the surfactant is all you want, then get a cheap brand, so you aren’t paying for the enzymes and oxidisers. But did they say why you should use one of these? What do you want to clean off the marble?

    • Some of their products are good, and some not so. Their Shower Power is a good product, as it uses citric acid as the active ingredient, and I think their oven cleaner is an interesting concept that would probably work. But i don’t think much of their other cleaners -I sent them an email to ask them asking them some pointed questions about some of their formulas, but didn’t get a reply. And their marketing claims are right over the top….

  232. Hello Dr Chemical, I have just recently bought a new fridge. Unfortunately there was a sticker on the front of it and once removed left the sticky residue behind. In the fridge manual it says on no account to use anything but hot soapy water on the fridge but even with a lot of elbow grease, the sticky residue is not moving. Can you recommend another way of removing it please. I look forward to hearing from you.

    Thank your for your help. Judy

    • Use acetone. The fridge is baked enamel and it won’t hurt it. Moisten a paper towel and wipe it and it will come straight off. You can get acetone from any hardware store. Petrol will also work but of course it’s very smelly.

  233. We recently camped out for a week at Wyangala Dam with our pre-owned white painted (outside) aluminium tinny. It has previously been in salt water only. There is now a brown stain on the hull which we cannot clean off. I would appreciate any suggestions you may have on how to get rid of it.

    Thank you.

  234. Hi.
    We recently purchased 2 plastic carpet protectors for newly fitted carpets in our home office from Clark Rubber, December 2013.

    The smell is abysmal when you first enter the room.
    Obviously the odour dissipates when the door is open, but nonetheless it still lingers in the room.

    It has a chemical/plastic/rubber smell. We explained the situation to Clark Rubber and they couldn’t suggest anything to fix the problem.
    Should we request a refund or is there a solution to the problem?

    Appreciate your advice.

    Kind Regards,


    • Take them outside and hang them in the air for a seek or so. The smell are the volatile molecules that have escaped from the plastic. That means that they are no longer in the plastic, and once they blow away they are gone. The smell that you smell tomorrow are different molecules that have escaped. And there are only so many volatile (smelly) molecules in there. Give it enough air and they will all escape and the smell will be gone. And that’s why the smell remains in a closed room – the molecules can’t escape and finish up back in the plastic (or on other surfaces)

    • Try BAM Easy Off aerosol shower cleaner. But plaster is porous, so the stains soak in, and are very hard to remove as a result. I’d paint it…

  235. Dr Chemical, Would you please let me know if there is an equivalent to the Procter & Gamble product Dawn Dishwashing Liquid Original Blue in Australia?
    P&G list Dawn Ultra on its Australian Web site with a list of ingredients.
    The many articles I have read on the Web for boat cleaning and Sunbrella fabric cleaning all refer to Original Blue Dawn Dishwashing Liquid. Is Ultra only a concentrated form of Original Dawn?
    Many of the \’simple\’ chemical product suggestions I have used to clean my boat come from the book – Quick & Easy Boat Maintenance by Sandy Lindsey. The author advocates bicarb soda for fibreglass and lime juice & salt for stainless steel but also recommends Dawn for many cleaning tasks. Sunbrella also recommend it for boat canopy fabric.

    • I’m not familiar with that particular P&G product, but it’s unlikely to be significantly different to other brands such as Finish. But dishwashing liquids in general are an excellent option for cleaning things that have been exposed to sea salt. The reason is that they contain builders – chemicals designed to remove (mineral) water stains from glassware in your washer.
      As for lime juice/bicarb, there is nothing special about that whatever – the citric acid in the lime juice will react with the bicarb to produce fizz, hence giving the impression of cleaning. But the reality is that any cleaning effect of this concoction is simply the scouring effect of the salt. A much better option would be washing soda (soda ash) used as a powder cleanser

  236. My son (3.5 yrs) and I drew with whiteboard marker on our white fridge door (mine was a shopping list and his was his version of a shopping list) and now I can’t get the writing off. After an internet search I have tried bicarb soda, Orange Power, Isocol, eucalptus oil, bleach, nail polish remover, toothpaste and WD-40 to no avail. I can get it off by rubbing very small patches at a time with my usual kitchen cleaner (bicarb blend Greener Cleaner from local company at but am worried that the scrub is (further) damaging the surface of the fridge door. Can you suggest anything?

    • The difference between a whiteboard and any other surface is porosity. A whiteboard is nonporous, and the pigments in the ink are separated from the surface by a silicone layer, so it is easily wiped off. Also, the pigments are not all the same. Black markers are the best and red are the worst, with blue and green in=between. That is, with red markers the pigments work their way through the silicone coating and can attach to the surface underneath. And if the surface is porous (like the baked enamel on a fridge) you can get permanence, even after it’s wiped off. The best solvent to remove it is acetone. If that doesn’t do it, nothing will

      • Further thoughts. It has now probably soaked into the baked enamel finish, so getting it out won’t be easy. You’ve got two approaches – destroy the pigment, or suck it out. But both approaches will involve either laying the fridge on its back or removing the doors.
        First approach, buy some pool-strength chlorine bleach (12%), and get an eyedropper. Using the dropper, squirt a trail of bleach directly on top of the marks, and then leave for a day or so. They should fade or dissapear.
        Second approach, sprinkle a trail of washing soda on top of the marks, then wet it with White Spirit. Leave it for a day and see if the white spirit draws the ink out of the paint. Re wet with white spirit if necessary, but it won’t evaporate much

  237. Hi Doc

    You are amazing because you give so much advice to people for FREE! – Thank You :)

    My shower screen drives me nuts. I’ve used a steel and copper powder cleaner on the glass to clean it which was quite good (sulphamic acid 100g/kg) but there still seems to be marks. Don’t know if is is “etching” or what not.

    1) Would the next step be to try hydrochloric acid and if so at what dilution? Or am I wasting my time, too dangerous etc etc?

    2) If the glass is etched is there a way to remedy this?

    Thanks heaps for your advice


    • Unfortunately if it is etched (which it sounds like) there’s not much you can do about it. You could try scrubbing it with kitten #2 cutting compound, which will improve it, but it won’t be perfect.

  238. Recently my daughter tried to prank a friend by putting store-bought pancake syrup on her friend’s car and TPing it. The owner’s reported it to the police, and they are also saying that it blistered the paint and so the new paint job will cost near 4000$, making the little prank a felony if pressed. of course even though they haven’t said they will report it if we don’t pay they want us to pay. I am fine paying for legit damage, but I just don’t see syrup blistering the paint. any knowledge on this? I think the real thing is that they put some chemical on it trying to get the syrup off and THAT was what ruined it. We are willing to pay for detailing, carpet cleaning ( even though doors were locked and nothing put inside), etc. Thanks for any help on this.

    • Pancake syrup is just thickened sugary water, and couldn’t possibly damage car paint – even older type acrylic paint. How old is the car – modern cars have either baked enamel or two-pack finishes, and are resistant to most (if not all) household chemicals. Something sounds dodgy here

  239. Hi Dr Chemical. I have brown build up at the bottom of the toilet and up the S bend. I can scrub it off but I cant get up the S bend to remove it. Can you sugest anything?

    Cheers Evan

    • yes – use wet and Dry abrasive paper.. It’s ferric oxide that is ingrained into the porcelain and there is no chemical way of removing it

  240. Hi, We have a stain on our poured limestone, which is composed of Vinegar, Vanilla Essence and sugar (home made fly repellant), any ideas on how to remove?

  241. Thankyou for recommending easyoff Bam. It has been the best cleaner of my bathroom in the past. My question is, can you recommend a product which will coat my 2 new bathroom shower glass screens which may protect them & make cleaning easier?

  242. I have stains on a mattress that I would like to try and clean/or remove. Not sure if it is perspiration. What is the best way to do this

  243. How do I remove cement please that was splattered on glass by a cement mixer and so finely that it was not noticed by me until recently. That is it has had a couple of years to harden.

    • Hydrochloric acid will get it off. Dilute it 1:1 then put some onto a rag and rub the window. Wear a rubber glove on your hand while you do it. It has a very strong vapours but it’s not toxic, so don’t worry if you get a whiff while you’re doing it

  244. Hello, I am a student and wear a white collared shirt every day. Around three years ago the collars of my shirts began to fray. I got new shirts. The collars of the news shirts ripped three years later. Originally the cleaners said that maybe the rubbing of the collars was causing it to rip. Now they say that commercial machines are rough on the shirts. Additionally, I was getting my shirts back with starch even though I was requesting no starch. I decided to buy non iron shirts that I could launder at home, hoping that would make my shirts last longer. I understand that I am going to have to pretreat the collars to get the sweat stain out. I would like to pretreat it in a way that the collars will not get damaged from the pretreating so that my shirts could last as long as possible. I read about using shampoo, tide detergent shout, oxiclean clorox etc. What is the gentlest, but yet effective way to pretreat the shirt that will ruin the collar the least. Does pretreating wear out the collar? I would like to treat my shirts in a way that will make that last the longest. I would greatly appreciate any help that you could provide. Thanks, Kenneth my cell is 9177537179

    • The best laundry prewash for this kind of thing is White King Stain Lift. It’s an enzyme based product that will remove sweat stains without damaging the material. It’ll also help prevent pilling

  245. Hi I have cleaned my shower grout with the Ajax and Bam products you recommend.

    It has mostly come up very nice, but some areas of grout have a noticeable reddish tinge to them…almost like the colour of iron ore.

    What could this be and what can I do about it?


  246. In the late 1970’s in Perth an alcohol based sunscreen was available which seemed to work better than the modern cream based ones. It was very easy to apply. Being alcohol based, it dried very quickly and didn’t leave any clammy greasy coating like all the modern ‘non-greasy’ types do. I remember that it was so good you could notice any spots you’d missed as they’d be very red that night.

    So, any idea why this product was discontinued? I vaguely recall that it was called Sun Block or Sun Smart – something like that and was supplied in black plastic bottles with red caps (similar to ‘Baker’s Fluid’ soldering flux!).

    My own theory is that they banned it simply because they found out I liked it. Everything I like meets this fate.

    • It sounds like Sea & Ski Block Out – yes, I remember it too. It was probably discontinued because the companies that make these products want to sell you as much water as they can, and they can do that by making an emulsion (about 90% water), which is what any white cream or lotion is. And it’s a lot cheaper than selling you 100% alcohol. Pity, I likes it too. Also, with an emulsion, they can create the effect of it “rubbing in”when the white disappears and it goes clear. In fact, all that has happened is that the water in the emulsion has evaporated, leaving the oil behind

      • Thanks for that reply. I’m starting to think it was called ‘Natra Sun’ – that’s if my rum soaked memory has any cells left. Seems a shame that they make modern sunscreens so unpleasant to use while urging us all to use them.

        • Yes, I agree, but it’s a modern trend. Fly sprays and laundry prewashes all used to be solvent based, but are now all water based emulsions. I’m afraid the almighty dollar rules.

    • Easy Off Oven cleaner (or any oven cleaner). Spray it on, allow 5 minutes for it to react, and then blot up with warm water and a towel

    • Well, you can’t go past bleach for that. But buy it from pool shops, where it is 3x the strength of what you buy from the supermarket. Dilute it by a factor of 3 and tip a litre or so down and see how you go