“From what I have read I think I may have drain fly larvae in my jacuzzi jets”, writes this reader in her submission regarding the organism pictured below. “They are dark brown and when looked at through a magnifying glass, they look like tiny millipedes. Can you please confirm? Thank you!” Immediately off the bat, can we say that these are indeed drain fly larvae: their long, thin dark bodies and tapered ends point to this conclusion. Likewise, the location they were found in matches up with the behavior of drain fly larvae.
Drain fly larvae, as their name suggests, are the larval forms of a species of fly that tends to live in, and come out of, people’s drains. The adult flies are also commonly referred to as moth flies, because of their stout, furry bodies which lends them a moth-like appearance. The mother fly lays her eggs on the thin film that forms in drains, and when those eggs hatch, the larvae are free to roam about the drain and bathroom in search of food, which mostly consists of decomposing organic matter: of which there is a lot in a drain, especially ones that are not cleaned often.
The best way to combat a drain fly infestation is through hand-picking the larvae when spotted and moving them to another location, and through preventative measures: keeping one’s drains regularly cleaned. The most basic way to do this is to pour boiling water down one’s drains, followed by a cleaning agent (eg. bleach), followed by boiling water again, with ten minute intervals in between each step. Of course, there are many other methods one can use: some people prefer using baking soda and vinegar. Similarly, if our reader notices the film forming in her drains, scrubbing that away will prevent drain flies from laying their eggs there. Additionally, as we are sure our reader’s research has told her, drain fly larvae are not a threat to human or animal health. They are not parasitic, and they do not bite, sting or secrete harmful toxins. Likewise, despite living in the drain, and basking in bacteria, drain fly larvae do not spread diseases or pathogens.
To conclude, the dark brown worms our reader has been finding in her jacuzzi are indeed drain fly larvae. They are nothing to be feared, though an infestation of them can clog the drains, so it is best to tackle it head on. We hope this helps, and we wish our reader the very best!
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