I used gnatrol on my peace lily that had a pretty good infestation and both of the SNS products on the MJ and had good luck with both. Haven’t seen a gnat for weeks but, use the stickies anyway just in case.I'm on it! Ya gotta get on em' as soon as you see even one! I've never had them get out of control, thank goodness. I use the hydroton clay pebbles to help prevent them laying their eggs in the soil, and I really think it does help. I believe I used diatomaceous earth as a top layer on the soil in a couple of grows as well.