How to Clean Tough Toilet Stains

Quick Column Summary:

• Toilets badly stained
• Clean without damaging toilet
• Reasons for staining
• Use an oxygen bleach

DEAR TIM: I've moved into an existing, but new to me, home. When we inspected the house a month ago, the toilets looked good. But now, they're stained. They look horrible. This house is on a septic system so I'm worried about what to use to clean the toilet. I've scrubbed with a toilet brush and a hardened white deposit that's deep in the bowl won't budge. Should I just purchase new toilets for the house? Amanda B., Wallace, NC

DEAR AMANDA: Toilets can be stained from all sorts of things other than body waste. I'm a master plumber and I've seen all sorts of toilet staining. Over the years, I've developed a process to remove just about every stain known to man or woman.

Let's start first with what you shouldn't do. Do NOT use any metal scrapper, spoon, rod, tool, etc. to try to clean a toilet. The metal can damage the thin clear glass coating on the china. Only in rare cases have I had to resort to using a piece of wood to help scrape stubborn deposits from a toilet bowl or the holes under the rim of the toilet bowl.

Stains can be caused by minerals, bacteria, or organisms that are in the water or start to grow in the toilet bowl. The hardened white deposit you describe is probably lime or hard water deposits. You'll be able to get rid of that with some careful work.

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This stained toilet doesn’t need to be replaced. It just needs some oxygen bleach, some soaking time and a scrubbing. Photo Credit: Tim Carter

At my own home, we have issues with an orange bacteria that loves to live in our toilets. Our drinking water that supplies the toilets with fill water has been tested for purity. I have no clue where this orange bacteria comes from, but it appears to be harmless. If you don't clean the toilets on a regular basis this bacteria can bloom within a few days.

The lime deposits tend to form much slower unless your water is extremely hard. The issue with lime deposits is they can interfere with the flushing action of a toilet. Over the years, hundreds of my readers have reported toilets that used to flush great but now don't work well.

The flushing problem can be traced to partially clogged toilet rim holes and the syphon jet hole in the base of the bowl. For a strong flush, the water in the toilet tank needs to flow rapidly into the bowl through these holes. Clogged holes slow the water flow meaning the stored finite energy in the tank water is dissipated over a greater amount of time. This means a weak flush.

Because you're on a septic system, you don't want to introduce any cleaning products that contain chlorine bleach into your septic tank. Look on the product labels for either chlorine bleach or the chemical sodium hypochlorite. They are one in the same. This chemical will kill off the beneficial bacteria in your septic tank. This bacteria is what breaks down the solid waste.

opens in a new windowI prefer to start my toilet cleaning process with opens in a new windowoxygen bleach. This is a powder you just pour into the toilet bowl. You only need to add a tablespoon. I do this and walk away from the toilet for about 30 minutes. This gives the product plenty of time to dissolve.

As the oxygen bleach dissolves, it releases countless oxygen ions into the water that work on their own to clean many stains. Those it can't clean it usually softens up so you can defeat them with a standard toilet brush. Your septic system will love the oxygen bleach as the oxygen helps the bacteria in the tank thrive and survive.

Lime and hard water deposits can sometimes be removed with hot white vinegar. Vinegar is a weak form of acetic acid. You need an acid to dissolve the lime deposits that can, in time, become as hard as rock.

If the white vinegar doesn't work, you need to use a more powerful acid. I've always had success with muriatic acid. It will not harm the china toilet, but its fumes are very toxic and the liquid acid can and will burn you. You MUST read and follow all the safety warnings on the product label.

You don't want to put this acid into your septic system or into a municipal sewage system. This means you need to add it to your toilet bowl when the water level in the bowl is minimal. You can achieve this by pouring a bucket of water rapidly into a toilet bowl. You'll see the toilet flush, but it won't refill since you didn't take water from the tank.

Mix one part muriatic acid to five parts water and pour this solution slowly into the toilet bowl. Add just enough to where the water level comes up to the normal level in the bowl. If you and any extra, it will go down the drain line towards your septic tank.

Let the acid solution sit in the bowl for hours. Lower the toilet seat cover to prohibit animals from playing or drinking the toxic solution. Open the bathroom window to vent the fumes. Close the bathroom door and put a sign up warning others about the toxic brew in the toilet. Do NOT use the toilet during this process.

After the soaking is complete, look to see if the hardened lime deposit is gone. If not, use a wood dowel stick to see if you can't break the lime apart or chip away at it. Wear rubber gloves, old clothes and full goggles over your eyes. Do NOT flush the toilet. The acid solution needs to be scooped from the toilet bowl, neutralized and then discarded outdoors. The acid manufacturer will have instructions on the label telling how to neutralize the acid.

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