Currently running 6 23watt CFLs for veg with only a cracked open cab door and a processor fan for circulation (no powered exhaust or intake) - temps stay a pretty consistent 74-77F. That's why I thought maybe with a 50 CFM I could get away with the 12 30watters, but RoughRider makes a good point. I'd still really like to run the 12 30watters but maybe I'm getting a little greedy for lumens? Just really want a decent sized, good quality crop.