Got this one handled a few weeks ago...when it comes to aphids Azatrol is nearly instantanious in its effects..talked to a coop owner of mine that supplies clones in the area. We were going back and forth between using a Dr Doom Bomb and the Azatrol.
Since the room wasn't that big at all 10 x 10 and since I didn't really want to deal with the clean up of the bomb that gets into everything, I decided to use the Azatrol that I had on hand and made sure that the hudson sparyer that I used was cranked up well so that I could get a signigicant amount of pressure when sparying UNDER the leaves which is where most of them are hangin out.
I waited until the lights went out and used a green light so it wouldn't affect the light schedule of the grow. Actually, you could do this just prior to the lights going out and get the same results. Anyway, I sprayed the hell out of them (top and bottom) and the next morning they had been stopped in their tracks. Keep in mind, I caught them early, I needed a magnifiying glasss to see them and even then it was tough, but aphids they were, no doubt...love the Azatrol..shits expensive but no more aphids...
BTW, just to make sure I didn't get a reaccurance I've been using
Azamax which allows you to use it right up to harvest according to the directions and they'r both natural and not harmful to the plants...one a week..haven't seen a gnat or aphid since and they're all happy....no bugs!