I am working with a cabnet. 20" deep 36" wide and 5' high. I have a 400Hps with a noncooled reflector and and elicent 6" fan for air flow. there are 5 2" pvc passive intakes. Its painted flat white on the inside. The temps vary since it is out in the garage. can get into the 50'sF in the cab and if I turn the fan down enough the mid to upper 70's but I keep it around 70.

I am getting ready to put some good genetics in there and want to make sure I am doing everything I can to optimize the space.

What have you found that helped your cab produce?
What are others yeilding out of simular space? The last grow, granted bad genetics was pretty sad. The most I have yeilded off one place has been about 2o's. But I have only ran bag seed and some cheep breeders seeds.