my box size is 48''hx31"w'x96"l. i use a 50 cfm fart fan, not sure of the brand. air is cycled completely in 2 mins. i keep a large dog in the room (cheap co2 generator ) so i constantly have co2 going in and stale oxygen comin back into the room as i run the fan 24/7.

hope this can be of some kind of use... its 4am and i don't know what i was about to say, so...

love, kp