Hi, I'm growing too and seem to be in the same predicament. The leaves on my plants are also doing the same thing only my temps are lower. I asked a friend who has been growing for some years and he metioned the ph can sometimes cause drooping. I don't know if this is the case though. The purple I was told came from the cold. I was also told on another site that it was over-watering but i'm positive it is not that either.
Sorry I can't help more.
Big Al