Black Worm in Toilet

Without a photo, it is impossible to identify this worm with certainty. Based off the description, we think he may be dealing with black soldier fly larva, often referred to as BSFL. BSFL are up to an inch long, and thick with rounded heads and pointed tails. This fits our reader’s description quite well. We also have had a handful of readers in the past who have found Black Soldier Fly Larva in their toilets. BSFL usually feed on decaying matter and are often found in compost bins or dead animals. It is unusual that BSFL would be found in toilets, but perhaps there is some organic matter tucked away in the toilet or piping system that is attracting these pests. We recommend cleaning the toilet thoroughly, and perhaps looking into hiring a professional if the larvae don’t go away.

As we mentioned earlier, without a photo it is difficult to know for sure what kind of worm this is. We have included one of our own pictures of black soldier fly larva, so that the reader can compare.

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Also, although very unlikely based on the description, it is possible that the worm came out of the human in the feces. If the reader believes this is a possibility, he should not hesitate to seek medical attention!

In conclusion, we believe our reader discovered a single black soldier fly larva in his toilet, and we wish him the best of luck getting rid of the infestation!

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Black Worm in Toilet
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Black Worm in Toilet
A reader wrote to us about some worms or larvae he discovered in his toilet bowl. The black creatures appear one at a time and move slowly. They are about 1 inch long by ¼ inch wide, and are round on one end and pointy on the other. The reader also said that these pests only inhabit one of the toilets in their house, but the other toilet is not being used currently due to a small crack on it. The out-of-use toilet has weed root intrusion, and they keep bleach in the bowl and the water shut off. The reader included some additional information about his septic system, but we won’t include all of it because it isn’t pertinent to figuring out which type of worm this is. Our reader is unnerved with the daily presence of the worm, and hopes we can help get rid of it.

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