How to Clean Calcium Deposits From Your Toilet Bowl

By: Alia Hoyt

That's right -- they're just calcium stains, not something ... worse.
That's right -- they're just calcium stains, not something ... worse.
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Modern civilization wouldn't be all that modern without the toilet bowl. No longer must we crouch precariously in outhouses or dispose of icky chamber pot contents. I actually believe that indoor plumbing tops pretty much any invention out there, including electricity. But it can still be more than a little annoying when the toilets you appreciate so greatly fall victim to dreaded calcium deposits. Fortunately, calcium stains are typically fairly easy to eliminate with a little elbow grease and a handy solvent or two.

Before we get started on the "how-to" portion, it's always important to know a few facts about the stains you're going to be attacking. First of all, "calcium deposit" isn't code for anything gross. In fact, they're exactly what they sound like -- a build-up of calcium and other minerals commonly found in your home's water supply. The toilet is a prime place for calcium stains because there's always some water hanging out in the bowl, just waiting to cause problems. Calcium stains build up over time, but it often feels like they appear out of thin air overnight, resulting in an unsightly brownish/orangish/pinkish ring around your once pristine toilet bowl.


Calcium deposits tend to be bigger and badder in places with hard water or well water because there's more lime and minerals present in the water supply. In fact, 85 percent of water in the United States is hard, so it's likely that you'll battle more than one calcium stain in your lifetime. Calcium deposits aren't limited to the toilet, unfortunately. They can run rampant anywhere water flows, including your sink and shower doors, walls and shower head.

There are ways to keep calcium deposits from happening or getting out of control. First, you could install a water-softening system in your home. Unfortunately, those are seriously pricey, so you might not have room in your household budget. The cheapest (and most logical) method is probably just to tackle any calcium stain the instant it starts to appear. Much like tartar on your teeth, the longer you let it build up, the harder you'll have to work to get rid of it.

If your bowl is already awash in calcium stains, fear not! Check out the next page for helpful tips on how to remove them quickly and easily.

Tips for Removing Calcium Deposits From Your Toilet

Even if calcium deposits have taken up residence in your toilet bowl, there's no need to throw your hands up in the air and purchase a new one. Instead, employ one or more of these techniques, and you're sure to see some squeaky-clean results. Well, for a toilet, anyway.

First, try the green route! A mild, natural acid, such as lemon juice or vinegar, can be very effective at nipping calcium deposits in the bud. Depending on the severity of the stain, the liquid might have to be reapplied and scrubbed vigorously several times with sandpaper or a rag.


Another option that many DIY experts swear by is plumber's cloth. Available at any hardware store, you can just use a section with plain old water to make stubborn stains disappear.

If you don't mind a few common household chemicals, pick up a bottle of commercial toilet bowl cleaner for the task. Some users prefer to drain the toilet bowl first because it prevents the water from diluting the power of the cleaner. Tank drop-ins are also effective at cleaning and preventing stains, although it might take them some time to completely erase the blemishes from your bowl.

If none of the easier options are doing the trick, there are a couple of riskier ways to get the results you desire. For example, muriatic acid can get rid of calcium deposits in mere seconds, but it's also very hard on porcelain and dangerous to use if you don't know what you're doing. First, take care to make sure the area is well-ventilated because of fume risks. Also, be sure to wear eye protection, rubber gloves and clothes that cover your skin completely. Then, pour 5 gallons or so of water in the bowl, followed by the slow, careful addition of 12 ounces of muriatic acid. Next, use a toilet brush with a long handle to carefully spread the solution around the stain. This step might have to be repeated several times over the next hour or two, but doing so should completely eradicate the mark. If you leave the room at any time, take care to close the lid and safeguard that no child or animal can come in contact with the water.

Another last resort option is pumice stone, available at many dollar and hardware stores. Simply use it with plain water to scrub out the stain, but do so very carefully. The harsh stone can damage porcelain irreversibly, and you don't want to trade one unfortunate appearance for another.

Lots More Information

Related Articles


  • Better Homes and Gardens. "How do you remove calcium/lime deposits from water fountains?" 2012. (May 30, 2012).
  • Braff, Danielle. "Hard facts about tap water." Chicago Tribune. April 25, 2012. (May 30, 2012).
  • Carter, Tim. "Muriatic acid is best for removing stubborn toilet bowl stains." August 12, 20120. (May 30, 2012).
  • Oz, Mehmet, M.D. and Dr. Michael Roizen. "Hard water can be bad for plumbing, good for you." Feb. 15, 2011. (May 30, 2012).