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Toilet Smells Like Mold? What it Means and What to Do

You walk into your bathroom and smell mildew or mold. When you flush the toilet, it gets even worse. Why does your toilet smell like mold? There are a few places where fungus or mold growth may be hiding. Here’s where you can find it and how you can clean it.

Nearby the Toilet

First, it doesn’t make any sense to dip into the toilet if the mold problem is nearby. Sometimes the rush of air from the toilet flush is enough to make you think the problem is the toilet, but it isn’t. Look for mold and mildew near the toilet, in the shower, on the bathroom ceiling, and the tiling. If you find mold, clean it with a diluted bleach solution and check on it regularly to prevent re-growth. You can reduce the odds of growing mold in your bathroom by increasing ventilation.

Clean the Toilet Bowl

If the mold is really in the toilet, the most common culprit is the bowl itself. Take a look inside, do you see any black or green streaks that might indicate mold? It could be hiding under the rim of the toilet too. Invest in some high-quality toilet cleaner and follow its directions to really clean the bowl. Use a specially shaped scrub brush to get under the toilet rim. Clean it every few days until the problem seems resolved, and then clean it once per week moving forward.

Assess the Toilet Tank

If you clean your bowl regularly and it looks mold-free, then the problem may be in the toilet tank. Pop off the lid on the tank and have a look at the water quality. Do you see any green, white, black or brown growth? Any could be the mold culprit you’re looking for. You could have your plumber clean the bowl, or you could do it yourself if you’re comfortable with the basic parts of the toilet.

Connect the float to the flusher so that it won’t drop when the water level drops. Flush the toilet to empty the tank. Then use a cleaning spray to remove the mold. A heavy-duty spray that is meant to kill a large percentage of germs is fine, as long as your rinse out the cleaner afterwards. Once you’re done, release the float so the water returns. Flush the toilet a few times to rinse. You may have to repeat this process a few times over the next few days to ensure the mold growth has stopped.

Replace the Wax Ring Seal

When the wax seal on the toilet has worn out, it may allow small amounts of water to leak out of the toilet, which may allow for mildew or mold growth. You can have your plumber replace the wax ring seal to fix this issue.

Other Issues

If these fixes don’t fix the mold smell, there may be a more complicated problem. For example, a small water leak somewhere in the bathroom could be spurring mold growth. If you haven’t found your fix yet, it’s a wise idea to call your plumber to investigate the smell for you.