I live in Seattle and this problem started while I was on vacation at the end of September. I came home and found my bathtub full of moths. I think they are moths. All dead. I left the bathroom window open while I was away. It has a screen but there are some holes in it. The window faces the back yard.

Now this seems to be an ongoing thing and I do have my window tightly shut. About every 3rd day, I find 30-40 moths in my bathtub. I think I found out the time they arrive. Usually just as it starts to turn dark out. If I catch their act before they jump in the tub, I see them on the window sill fluttering around aimlessly.

I read where it was said they bread in the slug of the drain. I had my bathtub plugged but the overflow is open. Is that where they come in? Or cracks around the window? I'm thankful they are only in the bath tub but I'd sure like to solve this mystery.

I'll try to post a picture of the insect.

Are you sure there are moths? How often do you use your bath tub ?

One of two things could be happening:

1. It could be that sewer flies are entering tub due to dry P-Trap. If you don't use tub on every day basis, make a habit of turning water on for few seconds couple times a week. That will keep P-Trap wet and sealed, preventing sewer flies from entering tub

2. It could be that bugs are coming in from under the tub around loose overflow gasket. There should be an access door behind the overflow, on the other side of the wall. Open it, take flash light and see what condition the overflow is. Overflow part of the drain, and should be sealed to the shell of the tub so there should be no way for bugs to enter around the overflow seal. See if the overflow is tight to the shell of the tub. If not, replace washer.

Hope that helps

Milo