You want to figure the CUBIC feet of the box. There are 1728 inches in a cubic foot.
I'm guessing you will be running either CFLs or a T5 24" fixture.
It's a small space and a small heat load. The small fan should work fine. Make sure you have a good intake- intake low, exhaust high.
But ventilation is important no matter what light you use.
stinkyattic Reviewed by stinkyattic on . Ventilation What should be used for vent a 69"x25"x18". And how would I figure out the sq foot of this box? Would a 500cfs exhaust fan be to much? I have a choice of 40 cfs, 160 cfs, 210 cfs, and the 500 cfs. What would be recommended? Pudder Rating: 5