So I'm planning on constructing a dresser grow box, and I'm gonna be using two 120mm computer fans, 1 for intake, 1 for exhaust, with a carbon filter on the exhaust. How much will the exhaust fan be "hindered" by the filter, if I'm using the one described here http://www.rollitup.org/do-yourself/101248-best-diy-ez-walmart-carbon.html How much higher cfm should the intake be?
intake should have lower cfm's than the exhaust creating negative pressure. If the intake has higher cfms then you've got positive pressure and odor leaks out. What I'd do is use both fans for exhaust and open up some passive intakes. That will double your cfms. The only reason you'd want an active intake is if you're piping in cooler air from somewhere else, like a crawlspace or an a/c or something. The one time I used an active intake on one of my builds I ended up disconnecting it because it was completely useless. Better off placing all fans on exhaust. How much light you gonna put in there?
oh nice I had the exact same question. have u tried it yet? I want to do the same pc fan/wolfman zen filter combo but am afraid that the pc fan wont be strong enough to pull enough air through the filter...