Mysterious Worms are Drain Fly Larvae

A reader reached out to us about some mysterious worms he found in his toilet. He explained that he recently discovered the fourth worm over the course of a few months. He also finds just one single worm wiggling around in his toilet:

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He explained that he keeps his toilet area clean and even poured some bleach in his reserve tank. The discovery of these worms has been so unnerving that he has even visited a doctor to have bloodwork done. The doctor didn’t take a stool sample because he didn’t believe the worms were coming from our reader. While this made him feel a bit better, he is still feeling a little uneasy about these mysterious creatures. Especially since he returned home from the doctor to find another of the creatures in his toilet:

We are happy to deliver some good news to our reader. We are very confident that these mysterious worms are not coming from him, and are in fact not worms at all but larvae. We believe the “worms” he is discovering in his toilet are drain fly larvae! Drain fly larvae are extremley common household pests. A drain fly larva has a translucent body with a black stripe running down its back. It has a clear black head and a black retractable breathing tube, which you can clearly see on bottom end of the larva shown above.
Our reader said he kept his toilet area clean, but he probably hasn’t scrubbed out the drain in a while. Drain fly larvae feed on the decaying organic matter that builds up in drains. The adult flies also lay their eggs in this grime, so if he can successfully clean out his drain he will have gotten rid of the breeding and feeding site for these annoying visitors! To clean, he should use a pipe cleaning brush and a cleaning agent gel that is specifically designed to get rid of organic matter.
In conclusion, one of our readers discovered some mysterious worms in his toilet that we have identified as drain fly larvae. We hope this article brings our reader some peace of mind, since he was very concerned about where these creatures were coming from!
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Mysterious Worms are Drain Fly Larvae
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Mysterious Worms are Drain Fly Larvae
One of our readers discovered some mysterious worms in his toilet that we have identified as drain fly larvae.

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