I'm trying to work with what I have allready.I have a 8", 350 cfm exhaust fan from a small greenhouse and one of those little Stanley blowers that manual says 3 speeds 190/260/310 cfm's.Is BEST way to have stanley blowing thru 6" duct(total 8' long)thru cooltube and out.AND to have the exhaust fan pull through a diy square 10" carbon scrubber directly no duct work?I have 120lbs of activated carbon in a tub.Room is 36"long,30" deep and 85" high with 400 watt dual mh/hps.Thanks ahead.