I've turned off the fan, I'm going to put any plants affected downwind and away from the others. A local shop said that I probably have two problems:
1. Wind burn from the fan and that's unlikely to recover.
2. Powdery Mildew or spider mites as their eggs are white and on top of the leaf - news to me about the white on top of the leafs
I just today noticed one plant with white flakes on the top of the leaves. I don't know what it is, but it wipes off.
I'll get some pics of that soon.
The guy at the shop said to use something called 'Green Clean' and mist it over the plants. He says it's ok this close to harvest.
Right now, the fan is off, the a/c is on and I need soil so I'm going to talk to a few local shops and see what they say.
There is one other note, my home is concrete block and part of the remodel involved busting up some concrete. There as a 'cloud' a few times and it was the room next to the grow room. The walls are there, but not air-tight. This might have been some concrete dust, but the white flakes are new and the dust clouds were last weekend.
Again, I'll post some pics soon.
Karl, are you using a cool mist humidifier? I get the white flakes as a result of the minerals in the water forming as the airborne water vapor evaporates and the minerals precipitate in the air and get blown around by the fan...this phenomina ( spelling ) is harmless. IDK if i've ever seen windburn, I use fans bro, i like my plants to be moving all the time, as long as its not blowing on em continuously like a friggen wind storm, I seriously doubt the windburn theory. I do know that the dust bunnies that form on the fans will cause problems...another vote for cleanliness, and periodic cleaning is absolutely necessary. Just some ideas karl, the answer is right in front of us always, we just gotta go throught he process of elimination, kick out anything that goes against the fundamentals and drive on!