Thx. I have some diatomaceous eatth around that should also do the trick but i will use more of the bti first. I also applied nematodes but they took some time till i got them and were some days at room temp.2-4 inches of perlite on top of the soil is always my first solution for any sort of gnat. Always worth trying, because it's impossible to fuck up and harm your plants, and perlite is cheap. Little to lose. Just an idea.