Howdy alltatup, I had a problem with white flies and gnats a couple of years ago, but found what will stop them, Azamax. At the first sign of the little critters, I start using 10 ml/ reservoir and if there are any signs on the leaves, I apply a foliar spray to the leaves. The stuff is useable up to the day before harvest, although once it is used in the reservoir, it becomes systemic and helps stop further infestations. It is not cheap (I have found it for as low as $19/4 oz.) but it works on many different critters.