Thanks for all the replies.

As for the heat stress that makes some sense, it did seem like the problem was the worst with the plants that were closer to the light. The distance to the light was at least 20" but not more than that.

As for the mold question, I have had a mold problem before and this could a part of the problem. I did cut some the other day and when it smokes it makes kind of an odd crackly sound, is that mold?

I stayed pretty well on top of the nutes so I don't think that's it.

Thanks again yall!