Drain Fly infestation

Georgetta1

We have been infested by drain flies for a couple of years. They look like moths but according to google are a type of fly. They come up from the shower drains in both our shower rooms. We have tried everything - drain cleaning products, bleach, bread soda + vinegar + boiling water, fly sprays, moth sprays, fly paper but all to no avail. They died off for the winter but I see they are appearing again. We tried to contact the entomologists in the Universities to seek advice but they didn't return our calls. We're at our wits end. Any advice please?

Deanicus

The wiki article on them suggests that the likes of bleach and boiling water have little to no effect

https://en.wikipedia.org/wiki/Drain_fly#Pest_control

The main way to get rid of them is to get rid of their food source, which in this case is hair, skin cells etc in the drain.

I would first suggest you use a drain unblocker type solution (usually a caustic base) to try and liquify as much organic matter in the drains e.g. hair followed by a good hot water flush

Do that a couple of times to be sure

Then get a good pipe cleaning brush, take off the hair trap insert of your shower drain and scrub the drain as much as you can. Go as far in as you can

You probably would want to tackle one at a time and not shower in that room for a couple of weeks. If clear, do the other one.

Hopefully that will remove enough organic material in the drain so the next generation die off!

Georgetta1

Thank you, Deanicus. We will try cleaning with a pipe cleaning brush after using a caustic draincleaner. We have used a caustic draincleaner before but not cleaned the drain with a brush. Thanks for the tip ….hopefully this will be the end of the drainflies!