Removing Hard Water Stains From Porcelain?

I luv the look of my black Kohler sinks, but they show every hard water spot. I have the Kohler cleaner (which is kinda a cream/polish), which I use on the prep sink fairly often, and works great.

But my main sink (which is huge) pretty much only gets used for water servicing items, so the only thing that needs to be removed are hard water deposits. I can use the Kohler cleaner, but it seems like overkill (and a lot of work given the size of the sink).

My water is not very hard (from a TDS measurement), but after a couple of weeks you can see spots and a light whiteish glaze in some areas.

So is there a simpler, quicker method to keep the mineral deposits at bay rather than having to scrub the whole thing down with the polish?

I’m not sure about porcelain, but I used to use vinegar on my fiberglass shower. Wiping down after use also helps.

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Most hard water residues can be removed by relatively weak acidic solution like acetic acid or citric acid. White distilled vinegar (acetic acid) is probably most economic. Give it a try.

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Systematically wiping dry with some kind of microfiber cloth after each use is probably what would work best, that plus the occasional rub with diluted white vinegar.
I love the elegance of dark color sinks and bathtubs in hotel or showrooms or other people’s home but they are not for me: too much of a PITA to maintain.

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Thanks… I just did by soaking a Dobie pad in WDV and scrubbing the sink with it. It sort of worked.

A search online suggested the vinegar needs to sit on the surface for 5-15 minutes, which is doable on the bottom, but not the sides (don’t really wanna be applying that long to the sides as the Kohler polish would actually be quicker).

Any other thoughts?

This is true. It takes a couple of minutes to help the interaction and dissolving the mineral.
There are commerical home products which do a better job of “sticking” like Lime-A-Way, but white vinegar is just a much cheaper option (you can get a galleon for $3-4 from supermarket) and it is food safe too.

My suggestion is to put some white vinegar in spray bottle and spray at the sink and come back 1-2 minute later and do another spray. As long as you don’t have a lot of mineral build-up, it should be good enough. I don’t assume you need to do this more than once a week. This is of course useful not just for your sink, but even for other household gentle cleaning. What I like about vinegar is that it is inexpensive and food-safe.

Now, if you have a thick layer of hard-water/mineral build-up (like this water kettle), then one way to do this is to have a few pieces of paper towel soaked with vinegar and then let them hang on the side of the sink. But I seriously doubt your sink has gotten this bad.


By the way, some people don’t like the smell of vinegar. Citric acid smell nicer, but slightly more expensive – I did a rough calculation awhile ago, maybe 50%-100% more? You can buy citric acid powder and then dissolve it in water. Citric acid has the smell which we associate to citric fruits, lemons, limes, oranges…

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I luv vinegar!!!

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