Bmollyanswered grow question 2y ago I had issues with fungus gnats for literally years. I tried everything: repotting soil, mosquito dunks, rocks, sticky traps, you name it. They always came back… until using Trifecta Crop Control. Seriously, one application… GONE. FOR. GOOD! I did use it a bit stronger than they recommended, which I’m not recommending for anyone else, but luckily it did not hurt my plants. Love this product!