The Unexpected Item That Magically Cleans Hard Water Stains

New life for that very old toilet.

September 27, 2021
Photo by Julia Gartland

Recently, I bought a house. Yes, that’s a brag. But also, it is a preface to a real question: How do people house? After a decade in a Brooklyn one-bedroom apartment, there are so many things that I have to learn about it. Like how to clean a garbage disposal, how to properly load a dishwasher, and what to do with more than one bedroom. And then there are the more pressing queries, like—how do I get this far-from-new toilet to be less gross?

In Philadelphia, where the aforementioned house is, the water is pretty hard, which means that there’s mineral build-up in the bathroom, and that the bottom of the bowl of the toilet was coated in an extremely unappealing layer of brown-yellow gunk. When my partner saw it, he assumed it meant that the family in the house before us was a big believer in if it’s yellow let it mellow. But after attempting my usual toilet scrubbing methods—Scrubbing Bubbles and a toilet brush—I found out that hard water stains are a good bit more resilient than I’d hoped.

I tried Borax, and I tried baking soda, and neither did much—the stain might have gotten slightly lighter, but it was certainly not gone. And then I remembered an unlikely cleaning item recommended by the patron saint of clean homes, Jolie Kerr, who I would probably follow into war—if there was some kind of cleaning war. She has frequently extolled the virtues of denture cleaning tablets for everything from jewelry to pipes. And since denture cleaning tablets are a lot cheaper than buying a whole new toilet, I bought some online to give them a try.

Here’s how it worked. Before I went to sleep, I dropped six denture cleaning tablets into the bowl of the toilet (various internet sources recommended “a few” and since they come six to a packet, six it was). They fizzed on contact, in a pleasing, and slightly sinister way. Then I left them there as I slept, until the next morning when I gave the stain a scrub with the toilet brush, and voila—no more gross hard water stains. One of the toilets (a house now means I have more than one of these!) had a more stubborn stain, so I repeated the process again the following night. To my delight, the toilet was sparkling white and looked clean again.

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Top Comment:
“Is this much denture cleaner okay for a septic system?”
— Pat S.

Since denture tablets are remarkably affordable—I got a pack of 126 for $6—it’s also a really budget-friendly way to make sure your bathroom stays beautiful, with pretty minimal elbow grease involved. As for the rest of the house, well, that might take a little more work. But at least the toilets are clean.

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Laurie B. January 18, 2022
I used the denture cleaner and it was effective below the water line. I have a ring just above the water line. Any suggestions as to how to bring up the water level without the toilet flushing? Something to stop it up that will be easy to remove?
Sarina January 12, 2022
We had hard, iron rich well water for many years and the water in the sprinkling system stained the outside of some of my windows. Does anyone have any suggestions on how to remove it, I’ve even tried scrubbing with SOS to no avail. HELP
Erica B. January 12, 2022
The tip: fantastic. But "How do people house?" House is not a verb, and this is not a cute repurposing of that word. Ick.
Granny S. January 11, 2022
This is a great suggestion! I can’t wait to try it. I don’t have discoloration in my toilets but I have a hard water “ring”. Which drives me nuts bc I tried bak soda, peroxide, boiling water & a DW Tab. Nothing has helped so going to try this method for sure! Thank you!!
Amber January 11, 2022
I'm so eager to try this! My new-to-me, old house also has really terrible scale issues. I've tried everything from different cleaners to a pumice stick (which broke off into the toilet when my husband tried to scrub too hard) and nothing has worked particularly well.

For those asking about shower heads, sometimes I use rubber bands to tie a spent half lemon to the fixture, and it dissolves the scale.
FrugalCat December 7, 2021
The Works toilet bowl cleaner is the only thing that works on my super hard water clouded shower doors. For the toilet, I use a pumice stick.
scampbelld.84 October 16, 2021
I’m definitely going to try this! We have hard water here in Savannah, GA as well and I haven’t been able to find anything that takes off the hard water marks off the glass in our shower. Vinegar? Nope. Limeaway? Nada. Elbow grease? Not even. Anyone have suggestions?
Claudia October 8, 2021
Any suggestions on how to remove hard water stains from shower hardware, like the chrome knobs and shower head?
Raphaelle Z. October 8, 2021
Citric acid worked really well for me. Just be careful if you have marble anywhere close 😬
Claudia October 9, 2021
Thanks! Citric acid like a lemon?
Raphaelle Z. October 9, 2021
I use powdered citric acid. It’s food grade and you can easily find it on Amazon. You can also use it to make bath bombs and toilet bombs and sour candies 😃
I made a spray bottle with about 2tbsp of the powder in about a quart of water and spray that on my fixtures. If it’s really covered in stains I fill up a ziplock baggie with that solution and attach is on the faucet so that it is submerged. That dissolves the build up pretty quick.
Claudia October 16, 2021
Wonderful! Thanks - will definitely try this.
Hendrix1975 January 11, 2022
Try Weiman glass cooktop cleaner. Great for shower doors
Pat S. October 8, 2021
Is this much denture cleaner okay for a septic system?
jamcook October 7, 2021
For very hard to remove iron stains in the toilet , try WD-40.. it works amazingly well.
Daniel H. October 7, 2021
My wife and I just bought a house and we are also in a very hard water area. Every fixture has hard water deposits. One of our first major purchases was a water softener/filter for the entire house, so our water is now amazing. But we are struggling to get hard water spots off of some fixtures.

We used CLR on some things, but this house has a LOT of marble (nearly every countertop) and we don't want to damage the marble by soaking it with a harsh chemical like that. I am pretty sure denture cleaner (being a base, not an acid) will harm marble.

Anyone have any ideas if this is safe for marble? Or have a miracle method of removing scale from marble?
Raphaelle Z. October 7, 2021
My marble countertops are honed so I used some bon ami powder and a non scratch sponge to polish off the scale. It’s worked well.
Daniel H. October 7, 2021
Thanks! That's super helpful.
Linda T. October 7, 2021
Brilliant, I live in Philly, too, and it's insane! I will definitely try this. Please let me know when you figure out the best way to clean the inside of the dishwasher! Thanks!
D October 8, 2021
Good old fashioned powdered Tang (remember what the astronauts drank) is great for DWs. After seeing how good it worked, I never drank it again. Just imagine....
Raphaelle Z. October 4, 2021
I’ve been using citric acid with a lot of success, to clean hard water stains. Just have to be careful with marble countertops 😬😬
Bebe September 27, 2021
We’ve deployed the filter solution and the Apple cider rinse, but perhaps because she has eczema and the Philly water is so incredibly hard, she still struggles. In NYC, her hair is fine after shampooing!
AntoniaJames September 27, 2021
What a great tip. We don't have hard water problems, thankfully, but some of our everyday porcelain dishes have become a bit stained over time. I'm going to try this on them! Thanks so much. ;o)
Bebe September 27, 2021
Any recommendations for Philly hard water in terms of the shower? It’s really hard on my daughter’s hair and changes the texture of her hair and her ability to get a real “clean” clean!
Margaret E. September 27, 2021
Really good question! I've seen on various forums that you can install a water softening filter, which might be the trick, but I'm still figuring out that one myself!
Estie September 27, 2021
I use a cider vinegar rinse on my hair as I live in a very hard water area in the UK. I've been doing this for a few years now and it leaves my hair really soft a shiny and prevents a build up of scale or shampoo. I keep a plastic jug in the bathroom for the purpose and probably use a few tablespoons fill to the top with warm water that I pour over my hair. When my hair has dried there's absolutely no whiff of vinegar.
Estie September 27, 2021
PS If the smell of vinegar is too hard for your daughter to get used to you can try lemon juice too but you need to be careful about going in the sun afterwards as it can bleach the hair. Also, I don't wash the vinegar rinse out.
Michelle C. September 30, 2021
Hello from California, I just happened to see your post. There are also products called "clarifying shampoos," that may help.