One of my plants has been developing brown spots. The plant itself is almost 3 months old and is about 6ft. I've had it under 12/12 for awile with a 400w high pressure soidum lamp and the buds have developed real nicely. I started noticing the spots a couple weeks ago so I initially pruned the leaves that were affected. I thought it might be a PH problem or a difficiency of some sort so I bought a PH tester and some tiger bloom. My PH was a little high, but only about 7.0. With the Tiger Bloom added it goes down to about 6.0. I've been feeding them for a week now and the leaves have become a healthier green, but the brown spots have continued to come. I was wondering also if it was mold, but I've had the room de-humidfied for awile and the problem still exists. If anyones got any ideas it would be awesome. I'll probably be flushing the soil right after i write this so we'll see if that helps. I'll also post a picture in a few.