Has anyone ever dealt with limescale in a bathroom sink?

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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.)
 
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  • #3
Borek
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Limescale will bubble if treated with an acid strong enough.
 
  • #4
Wrichik Basu
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Limescale will bubble if treated with an acid strong enough.
But too strong an acid might actually destroy the material of the sink itself.

Maybe a moderate concentration is best.
 
  • #5
Borek
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Strong _enough_ was a very careful wording.
 
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  • #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.
 
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  • #7
Vanadium 50
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Those products are acids.
 
  • #8
CWatters
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Ordinary vinegar will attack limescale but not very aggressively.
 
  • #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.
 
  • #10
Stephen Tashi
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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!

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.
 
  • #11
Bystander
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"Lime scale," or soap scum?
 
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  • #12
symbolipoint
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"Lime scale," or soap scum?
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.
 
  • #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.)
 
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  • #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.
 
  • #15
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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,
 
  • #16
lewando
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Rust removers featuring oxalic acid work very well.
 
  • #17
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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.
 
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  • #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: .
 
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  • #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.
 
  • #20
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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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  • #21
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.
Don't think the OP expected the products to "work like on TV"! She states "hard to remove (you can scrape it, but it takes a lot of work lol)". As Mark and I stated above it is best to avoid these commercial products... they are not good for your health, especially if you are asthmatic or have allergies/sensitive skin. Additionally, they will affect and corrode metal/chrome bits in the bathroom (eg tap, waste pipe etc).
 
  • #22
symbolipoint
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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.
This is why some of the products come as a thickened (viscous) liquid, sticky, so that once sprayed, will stay in place, more or less, for a minute or two at least.
 
  • #23
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The process described by @Mark Harder is now done automagically in modern water conditioners. Once a month or so you dump a 20kg or 40kg sack of conditioner salt into a holding tank, and software does the rest. When brine is needed, water fills the holding tank long enough to saturate with NaCl, then the rest runs by itself. Once there's no more solid to dissolve, another sack is needed. I suppose recent models will email you when it's time to deal with that.
 
  • #24
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Apologies for the belated response everyone. Was very busy with a new summer job and had sort of forgotten about this thread I posted.

Limescale will bubble if treated with an acid strong enough.
Borek,
I've only tried using bleach and and distilled white vinegar on this "white stuff" that is in my sink and shower. I poured it on the white stuff (which means it only stayed on it for a few seconds, before going down the drain). I did pour a lot though and multiple times from small cups. I can't find a sink drain/pipe plug that fits my sink to allow me to fill it up and "soak" the white stuff for a long time, before trying to remove it. I think Home Depot has a stopper that fits, though. Going tonight to try to buy one.

Bleach seems to dry it out. The vinegar seems to "dissolve" some of the white stuff (like surface level only), but most of it remains.

With vinegar, something VERY weird happened, however. After pouring it on the white stuff and seemingly seeing some of it dissolve, I also immediately (upon pouring) noticed some tiny black dots that magically "emerged" on it. It made me wonder if the dots were underneath the white stuff and after dissolving the "top layer" they were revealed. Or, could it be the vinegar interacting with the white stuff produced these weird black dots?

In either case, I still get this white "growth" every 3-4 days. It "grows" very fast. I threw away a few sink strainers too, because the white stuff would start coating it after a while and the strainer would get all clogged up with the white stuff. If I do nothing for 10-14 days (i.e., don't use bleach of vinegar to pour on it, nor try to scrape it), the white growth will coat my entire sink probably. That's about the pace of its growth/advance. I have scraped a lot of it off thus far (sometimes after using bleach and sometimes without it) every few days, but not all of it in one sitting. It's very cumbersome to try to scrape it all. In any case, I think I once scraped it all off - maybe except for a small spot or two - and it STILL came back that one time after about 7-8 days and the build up process began again.

Not sure if it's causing my fungal and yeast infections, which I came back from dermatologist confirming today....I didn't tell her about the white stuff, but since I'll be seeing her in 3 weeks again, I'll ask then.....

***see pictures below***

A picture would be helpful in this case.
I have four:

2 pics of sink in question (you can see the white stuff and some black dots too that I talked about in my post w/ Borek above)
2 pics of our drying machine (weird black dots began appearing after using the dryer and the exhaust or whatever that thing is with holes is all black too)
--worried my clothes have fungus/mold/mildew and after washing it in the washing machine, it's getting spread in the dryer...

Is this possible?

S74YVuk.jpg


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  • #25
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continued from posts above

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"Lime scale," or soap scum?

Yeah, that's my question. I actually have no idea what it is. I even posited possible white mildew (it exists) and/or white mold (this exists as well).

So, you have:

a.) limescale
b.) soapscum
c.) white mildew
d.) white mold

or a combination of these four (and maybe even black mold, as small black dots have increasingly started form in the sink and a few even in my shower too, which can't be wash away...these are highly resistant black dots that just stay there)....

total mystery at this point....

edit to add:
One other point I'll bring up. Prior to pouring vinegar on the white stuff, the white stuff was quite hard in texture. It started out as a thin layer and would get thicker and thicker and was hard. Even after bleach (which dried it out as mentioned above), it would still grow in a hardened fashion.

After pouring vinegar, the texture was more "slimey" or damp and less hard. If I don't scrape it and leave it, it'll continue to "thicken up," while still remaining kind of "damp" and less hard. ...It's as if vinegar softened this white stuff.
 

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