Heya PC- hope yer well.

One of the big advantages of a thicker cell wall ( referring to another thread) is resistance to pathogens. The silica will boost yer plants immune system cross the board. Also makes it more difficult for sucking insects to pierce the wall (slowing them down), and for chewers to ,well, chew. Leonardite based silica supps are dirt cheap ( heh heh)- you should give one a shot. Silica Blast and Protekt work really well too.

But really, air flow and humidity are the big factors- Can be a real b*tch in a scrog @ canopy level. Do you have a fan under the screen? Maybe a couple of wall fans just blowing straight up?

Both the Serenade and the sulfur can be used preventatively.