You can try yellow cards for a start, but they're only good for a mild infestation. If you can get your hands on some Gnat Nix, that would be the best approach. Mix up a batch and use that for your nute water for a few days and you should be good to go.
I don't grow coco but I have poured a gallon of straight 3% H2O2 though a pot of soil and the plant came through fine.
Also, aim a fan at the soil line to keep them from landing on the pot. They don't fly all that well in a breeze.
I don't grow coco but I have poured a gallon of straight 3% H2O2 though a pot of soil and the plant came through fine.
Also, aim a fan at the soil line to keep them from landing on the pot. They don't fly all that well in a breeze.