Serenade and Fungaflor seem to be the best (or at least the most popular among pro growers) for limiting/controlling PM once you already have it.

Growroom humidity control (under 50% for sure) seems to be the most effective at preventing the start of PM. Fungaflor and sulpher burn both can help prevent the start of PM if used early and especially in conjuction with low humidity in the growspace. Sulpher burn can be a bit tricky and if overdone even a little bit it will burn the big fan leaves especially if you do it with the lights on (I have done this very thing - not good)
Max Blast Reviewed by Max Blast on . powdery mildew anyone ? so i have used potasium bicarb to somewhat control pm in the past. im interested in supher burner but as a diy sort of guy and frugle as well i look into homemade units with a can alight bulb and another can this looks easy and effective so i set out to gather goodies for the project .first order of busines vaporise some bud. i use the budda it has a heating element and heat control knob also it is round and acan fits on top of it nicely. my thought is to put some pellets in a can on top of the Rating: 5