To Suck or Blow, that is the inline fan question

I'm having heat issues in my grow cabinet, i'm using a booster fan. I'm going to have to upgrade to a higher power fan if I can't get it work right.

But currently, the fan is sucking cold air in and thru.

My question is, should I be pushing the air thru, sucking air thru, or what? Or should I just get the higher velocity fan and call it good?

You'll be much better served to use that one and only fan as exhaust. Cool air would come in passively through the hole you already have. If that doesn't work... get a bigger fan.

Ya, thats how it's set up currently, I"ve got the ducting stretched well enough, so I think it's going to require the other fan.

I have a dual side by side cabinet with a 250 CFM booster duct fan going right out the top of my box exhausting into my attic.This sits on the wall that divides the chambers,1 veg,1 flowering,passive air intake.I veg with 81 watts of CFL and flower with 150 HPS.I've never had a heat prob and the hottest it gets in the box is 80 degrees.This lil baby has 2 1/2 sq ' each side,4' tall.BTW growing DWC(deep water culture)
Got my medical MJ card.I'm allowed to cultivate 12 plants and have up to 2 1/2 Oz's on my person at any time.Say yes to Michigan.

Booster fans are easily defeated by more than a couple of feet of perfectly straight ducting. A better bet is a centrifugal, or vortex fan, capable of exhausting the volume of the room 2-3 times a minute if using hid lighting.
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