I used to have a 0.8 by 1.2 by 1.6 just a tiny bit bigger under my stairs it fitted in snug I used a 4 inch fan worked a treat was using a 600 hps
What I'd say using a hps get the biggest reflector you can .
I used a parabolic upped my yield
It's the outside squares you need to worry about you don't want sweet spots
But bro leds are the way to go
Top right hole was my outtake..straight into my kitchen lol
Bottom was my intake hole ..needed it ..4 inch ducting right into the tent had a silk screen jeep the bugs out ..the owl air going in was always cold .
I grew in that room no extractor could see black mold on the ceiling in the intake worked a treat
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