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Remove Black Mold From Toilet Bowl, Tank and Seat

At some point, it happens to everyone. You lift the lid on a toilet bowl only to be greeted by a ring of black mold. It could be in your home or in a friends’. You stare at it, wondering if you want to do your business, after all. You question if it’s even safe to squat down. If you’re at a friends’ house you have to deal with it, maybe by using excessive amounts of toilet paper. But if you’re at home, this is your wake-up call. You have to handle the problem and fast. In addition to its unsightly appearance, toilet mold can be potentially hazardous to your health, especially if you have allergies or are exposed to it for long periods of time.

What Causes Toilet Mold?

black mold in toilet bowlMold is a fungus that grows where there’s moisture. A good temperature (the same temperature range people prefer) and a food source are helpful, but the moisture is the real problem. All homes have spores floating around in the air, but homes with excess humidity are more likely to develop a fungal problem.

There are many possible reasons for the appearance of mold in your toilet tank or bowl. If you’ve been gone for awhile, the stagnant water can breed the mildew, particularly if human waste has sat along with it, after only three days. Think about your bathroom. The toilet, the sink, the shower: all of those produce moisture, so having mildew problem is very common. The very presence of your water is likely to attract spores. If they’re let sit for long periods of time, problems erupt.

If you have mold in a toilet or anywhere else in your home, it’s important that you remove it following the proper safety procedures. You should also have a professional come in to identify the source of the moisture so it can be eliminated to reduce the likelihood of future problems.

How to Remove Mold in a Toilet

Black mold removal needs to done correctly. Prolonged exposure to the spores is dangerous, so it’s essential that you take care of the problem swiftly and use the right equipment.

Before you begin, put together everything you’ll need: goggles, gloves, boots and breathing protection. Get bleach to kill it, borate and one other household cleaner. Open windows so that you’re not breathing in the bleach. If your bathroom doesn’t have windows, open the door and open doors and windows in other parts of the house to keep air flowing. After that, you’re ready to begin.

Step 1: Flush the toilet and drain as much water out of it as possible.

Step 2: Use a cleaner, such a spray bottle of vinegar or some laundry detergent, to clean the toilet and loosen the fungus. Flush. Repeat this step until you no longer see the toilet mold.

Step 3: Put a cup of bleach into the toilet and let it sit. Do the same with the toilet tank if you’ve seen evidence of a problem there, too. Leave it for 15-30 minutes. Do not add ammonia because the mixture emits a toxic gas. Do not add other household cleaners. Flush and repeat.

Step 4: Using a mixture of water and bleach (one cup of bleach per gallon of water), scrub down the toilet boil and tank while wearing gloves.

Step 5: Flush your toilet again and dry as much of it as you can. Flush again.

Step 6: Apply borate, which can be found in the laundry aisle at the grocery store, to your toilet bowl. This can prevent mildew from growing again.

Step 6: Clean up. Throw out any towels or brushes you used to clean.

Step 7: Wash your hands and face.

Preventative Measures to Reduce Future Outbreaks

black mold on toilet seatMake sure to clean your bathroom regularly with bathroom cleaners and anti-fungal sprays at least once a month. Wipe down your shower and use a good bristle brush on the toilet. Add the borax and don’t forget to check how the tank is doing.

You can use paint that will discourage mildew from growing on the walls, which is particularly useful for rooms with a high amount of humidity, such as bathrooms. You can paint over it with regular paint without reducing its effectiveness.

Consider purchasing a dehumidifier to reduce the amount of humidity in your home. If you can’t locate the source of the moisture, contact a professional to identify it for you.


Mold is dangerous and can cause health problems if it goes unchecked. Exposure can cause respiratory problems, sinus congestion, watery eyes, skin irritation, sore throat, coughing and asthma attacks. If you smell something musty in your home or suddenly start having allergy attacks, it’s possible that you have a problem.

If you find it, black mold removal is essential for your health because it can cause severe health problems, such as abdominal pain and dizziness, if you are susceptible to mold allergies or have a weak immune system.

The moment you notice mold in your toilet or bathroom, you need to handle it. Don’t wait. When it’s gone, be sure to do everything possible to keep it from returning.