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Has anyone ever dealt with limescale in a bathroom sink?

  1. Mar 14, 2018 #1
    If so, how did you know it was limescale and not something else....like white mold, efflorescence, etc.?

    I have some weird white residue that is building up on my sink and it is:

    a.) hard to remove (you can scrape it, but it takes a lot of work lol)
    b.) keeps coming back (granted, I typically haven't taken the time to scrap it all off...so there's some that's left over, b/c my arm gets tired...and maybe whatever it is just keeps growing)

    Just seeing if anyone has ever dealt with some weird white chalk-y substance in their sink that builds up....I even have something similar in my shower floor area too!

    (p.s. I'd be happy to post a pic too if that'd be helpful for recognition.)
     
    Last edited: Mar 14, 2018
  2. jcsd
  3. Mar 14, 2018 #2

    Wrichik Basu

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    A picture would be helpful in this case.
     
  4. Mar 14, 2018 #3

    Borek

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    Limescale will bubble if treated with an acid strong enough.
     
  5. Mar 14, 2018 #4

    Wrichik Basu

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    But too strong an acid might actually destroy the material of the sink itself.

    Maybe a moderate concentration is best.
     
  6. Mar 14, 2018 #5

    Borek

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    Strong _enough_ was a very careful wording.
     
  7. Mar 14, 2018 #6

    jim mcnamara

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    There are a lot of products meant to clean up accumulations of calcium salts. In the US, try CLR or any product next to it on the grocery store shelf. Read the label. If you are in Europe I'm sure @Borek can recommend something.
     
  8. Mar 14, 2018 #7

    Vanadium 50

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    Those products are acids.
     
  9. Mar 14, 2018 #8

    CWatters

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    Ordinary vinegar will attack limescale but not very aggressively.
     
  10. Mar 14, 2018 #9

    symbolipoint

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    Grocery-store and hardware-store products are formulated and available for removing such deposits from bathroom sinks. Also a soft abrasive brush might help. Not know what they are called, but may be made of some foamy-like plastic material.
     
  11. Mar 15, 2018 #10

    Stephen Tashi

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    I don't know how a mineral scale came to be called "lime" scale, but many white chalky deposits can be removed with lime juice. Cut a lime in half, squeeze a half on a chalky area and set it to rest on that area for half an hour. Then try scrubbing the scale off using the half-lime itself. That will confirm (or refute) the idea that the chalky deposit can be removed with an acid.
     
  12. Mar 15, 2018 #11

    Bystander

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    "Lime scale," or soap scum?
     
  13. Mar 15, 2018 #12

    symbolipoint

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    Lime scale is the hardwater deposits, like found in pipes and sometimes in vessels which are used for frequent or prolonged heating of water.

    Soap scum involves soap anions precipitating with the hardness cations, as might occur in showers, toilets (sometimes) and sinks.
     
  14. Mar 15, 2018 #13

    Tom.G

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    Yea, lived with it as a teenager with well water having 10 to 20 times the 'hardness' of municipal water.

    What is called 'lime buildup' or 'mineral buildup' is usually Calcium Carbonate (CaCO3), also known as Limestone and as Chalk. It's found in practically all groundwater and municipal systems in varyiing concentrations. If your water tastes a little like chalk, you have a significant concentration of the stuff.

    As mentioned above, the two standbys are Vinegar (Acetic Acid) and Citric Acid (lemon or lime juice). If I recall correctly, the CLR product is Citric Acid.

    If using Vinegar, you can sprinkle some table salt (Sodium Chloride) on with the Vinegar. This provides some abrasive action and reacts with the Vinegar to produce some Hydrochloric Acid (HCl), which is more agggresive than the Acetic Acid. (Not particularly dangerous that way. If you have eaten Fish-and-Chips with salt and Vinegar, that's what you taste, the HCl.)

    Whatever you use, leave it on to soak for at least several minutes. I've even applied a paper towel to the surface and saturated it with whatever acid I'm using to extend the soak time.

    Another possibility is to use denture cleaner but the active ingredient, Phosphoric Acid, may stain some metals. (Phosphoric acid is used to chemically prime Steel for painting (Phosphate treatment), it leaves a gray surface coating. It is also used to remove rust when sold as Naval Jelly.)

    If you want vicious activity, get some dry pool acid (used for adjusting acidity of swimming pools). Wet the surface and sprinkle it with a little bit of the acid crystals. Wear rubber gloves, old clothes, and eye protection if using this approach. Rinse area thoroughly afterwards. Don't get it on bare Iron, it will severely rust quite rapidly. Having some Baking Soda around for clean-up and emergencies is a good idea too. It sure is effective though! (Dissolves concrete too.)
     
    Last edited: Mar 16, 2018
  15. Mar 20, 2018 #14

    rude man

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    Another idea is to fix the leaky faucet that's probably causing the buildup ... :smile:
    You can get free replacement washers etc. from some faucet mfrs. I have.
     
  16. Mar 21, 2018 #15
    You can easily and cheaply obtain products desinged for this purpose at a local hardware store.
    They are usually moderate level HCl with a bit of scent to make it smell nicer,
     
  17. Mar 21, 2018 #16

    lewando

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    Rust removers featuring oxalic acid work very well.
     
  18. Mar 22, 2018 #17
    Investigate sulfamic acid. Don't know what is used in these days, but it was once popular in coffeepot cleaners, for descaling distilled water stills, and is one of the chemicals in CLR.

    What you might want to try is apply hypochlorite bleach to one area, and an acid solution to another. If bleach doesn't appear to faze it, but acid does, it is probably limescale.
     
    Last edited: Mar 22, 2018
  19. Mar 22, 2018 #18
    Forget the acids and formulaics, just get a new sink :cry: and install a water softener :kiss:. The former will make your sink shine like new and the latter will prevent limescale from accumulating. If you think getting a new sink is expensive and a bit drastic, consider the cost of the daily treatment with acid and what that does to your health :eek: .
     
  20. Mar 24, 2018 #19

    Mark Harder

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    Plenty of suggested methods for removing the stuff. I have to second and third the suggestion made by EarthCitizen. If the scale in your sink is magnesium and calcium carbonates, you are using water with high concentrations of the Mg and Ca. These are present in the form of bicarbonates that are formed in your aquifer the same way that formations in caves are formed. Water seeping through the limestone (or dolomite, or marble) contains CO2 in the form of carbonic acid, which dissolves some carbonates because it forms the bicarbonate salt, which is slightly more soluble than the carbonates. Upon exposure to air, the bicarbonate loses one molecule of carbon dioxide. That leaves very insoluble Ca and Mg carbonates, et voila, you are growing cave innards in your sink. Continue with the experiment, or get a water softener. If scale is forming in your sink, then it's also depositing inside all of your plumbing, which become increasing sclerotic, as in arterial sclerosis, just waiting for a bit of gunk to become lodged. Now you have no water at all.
    The water softeners I know from my youth contained a cation exchange material. I believe it was a sodium zeolite mineral. Divalent cations like Ca and Mg have a higher affinity for the exchange medium than sodium, so when your divalent-laden water runs through the exchanger, they replace the Na ions in the zeolite. Eventually, the exchanger becomes saturated with divalents and must be regenerated. Regeneration involves making a concentrated brine solution from NaCl pellets you bought at a hardware supplier and circulating it through the calcium form of the exchange medium. The exchanger is then rinsed with water and the solution of Ca, Mg chlorides are the washed down the drain. Since I was a chemistry enthusiast in my youth, the process wasn't as laborious as it sounds for me. It was one chore I didn't mind doing, and that was only every month or so. BTW, the scale probably does have some Ca,Mg soap in it. This particular gunk is another reason people use water softeners. The divalent soap scum forms on your body and hair when you wash, and is rather unpleasant and not the best kind of soap either.
     
  21. Mar 26, 2018 #20
    Commercial products work fine....the trick is to leave them in place and give them time to desolve the limescale. Don't expecte to just spray and wipe a few seconds later, real life is not like the TV adverts where it works instantly. Spray and leave in place for 10/15 minutes.
     
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