I actually have one of those and it's plugged in near the containers, but the gnats don't seem to want to come out of the containers and towards the light. If I can get the gnats out, they just fly right back in there and ignore the light.
I raise my own mealworms and over the last month or so I've had a growing problem with gnats in the mealworm bins. Specifically, they're in the bins with the adult beetles and I don't know how to get rid of them. I tried making traps with apple cider vinegar and a drop of dish soap but the...