Psst... We're working on the next generation of Chowhound! View >
HOME > Chowhound > Not About Food >
Dec 8, 2006 06:12 AM

Removing white powdery film from pots

I live in an area that has very hard water.

I do not use a water filter. After I boil water, particularly in a pot made of enamel, there is a very noticeable while powdery film left on the inside of the pot. Same thing with my stainless steel pots.

I have heard that the use of white vinegar will remove this mineral residue. What is the process - a teaspoon of white vinegar in a pot of boiling water, and for how long?

Is this white powdery substance calcium?

And yes, I know I should use a water filter. My tap (what?!) water tastes fine, so I don't find the need to use a filter, but I don't like seeing all this white stuff coating my pots. I do believe that filters would result in cleaner and fresher tasting foods, for the record.

  1. Click to Upload a photo (10 MB limit)
  1. Removing hardness from the water is more complicated than just filtering. The link below is a little too technical but gives useful insight:

    1. A weird but effective short term solution is denture tablets (Polident, efferdent--I buy the cheap generic drugstore brand and keep them under the kitchen sink for cleaning glass vases, etc). One tablet per two cups warm/hot water you use to fill the pot. Let them effervesce and then let them sit for a couple of hours. Rinse them well; that should work.

      1. Although removal of the calcium and magnesium ions that make water "hard" is not difficult technically, it does involve some equipment, which is available through a variety of companies that provide domestic water treatment services. Filtering won't help. Boiling with vinegar will remove (dissolve) the scale, as will treatment with any other acid. We have the same problem and I like to use muriatic acid (which is hydrochloric acid), but I have some background in chemistry and am comfortable working with strong and potentially dangerous chemicals, so I can't recommend that generally. A better alternative, and something that will work much better than vinegar, is any of the products that are designed to remove hard water scale from plumbing fixtures. I forget the brand names, but they're readily available in the cleaning products aisle of any supermarket.

        3 Replies
        1. re: FlyFish

          Are there any health risks associated with cleaning stainless steel pots with diluted (20%) hydrochloric acid? I mean despite thoroughly rinsing and scrubbing and boiling water and then spilling it before using the pot again for cooking.

          1. re: Driver

            No, not in the sense of lingering chemicals that you need to worry about. Hydrochloric acid is simply hydrogen combined with chlorine (HCl) and disassociates in water into hydrogen (hydronium, really) cations and chloride anions. Hydronium and chlorine ions are all around us constantly and pose no particular health threat. But, but, but . . . a 20% solution of hydrochloric acid is pretty serious stuff and can cause skin burns and similar problems. I was really referring to something more like a 5% solution, or even less. Don't forget that when you dilute a concentrated acid you must ALWAYS add the acid to the water, not the reverse, which will cause a vigorous physical reaction that could potentially spatter the concentrated acid onto places you'd rather not have it. The mnemonic they taught us in Chemistry 101 was "May his rest be calm and placid because he added water to acid." I can remember that from over 40 years ago, so I guess it worked!

            1. re: FlyFish

              Thank you very much for your answer. I was not sure if the acid leave some kind of residue on the steel (or create some dangeours compound) that cannot be washed away. And I will remember to add acid to water.

        2. I use soft scrub, I used to use BonAmi.

          Soft Scrub has a very distinctive odor, Bon Ami is a very fine powder, if you use it, be careful when shaking it out of the container, unless you want to be in a Bon Ami cloud.

          Don't use chemicals nor vinegar, there are cleaning products designed for your mineral rings. I use a lot of vinegar; laundry, water fixtures including the shower nozzle and cleaning my dog's stainless steel pans, it will take a lot more than a teaspoon of 5% vingear in a pot of boiling water. If you use strong chemicals, the rivets (fasteners) in your posts will corrode.

          For glass vases/wine decanters, I use vinegar and rinse with distilled water.

          1. I second the vote for using a (gentle) cleanser. In a pinch, I have even used ajax (!!! I know...I was desperate). Just scrub gently and the film will come off very easily and quickly. Rinse very well. I don't have enamel but this works great on my decent quality stainless pans.