For Fungus Gnats try this. Water with 90ml per gallon of Spinosad every 6 days, and water with 1/2ml per gallon of microbe-lift BTI every 3 days. After the first dose of the spinosad you should see a big reduction in flyers emerging. By the 3rd dose of Spinosad, and continued BTI, you should be good. If you start seeing flyers again treat with BTI right away, and you should be good. I only use the Spinosad in this manner when the fungus gnats were really bad. The flyers don't do any damage to your plants. The larvae eat roots.