Benzelsanswered grow question 3 years ago Yeah mossie bits are meant to work well and be kinda cheap, or you can get B.Ti - its organic and works on every bug that eats your plant. But its harder to get and more expensive. Or neem oil basically works on everything too. But Gnats can be a sign your watering too often too as they like it wetter, the wetter the better. So after you treat your plants let them dry out more and more often ok.