n00b ventilation question? I don't know...

kratos what the fuck are you trying to tell him? passive intake all the way.. y would u run 2 exhaust? thats plain stupid.. vent the light and exhaust the room all in one.. filter-hood-fan.. and the ipower 440 cfm fan is 70 bucks on hpsgrowlightstore.com...

You must have misread my post. I'm not sure how you're managing to use one 440 fan to both cool your lights and recirculate the air in the room because that just wouldn't work for me. The two exhausts aren't both for the box, that's way too much air being moved at a time. I have two 1000 watt hoods and they are air cooled from air coming in from outside of the box with a fan blowing air through both of the hoods and out of the box. The air going through my hoods does not come into contact with the room at all. This is why I have the second exhaust to circulate the air in the room itself and not just move air through the lights. If I didn't have the exhaust to blow air through the lights my temps would be a lot higher than they are now. And if I only pulled air through my lights then the air in my room isn't being ventilated fast enough.

I only use a 190cfm fan to cool my 400w light and circulate air in the tent. Been doing it this way for years without problems.

with 2 lights i could see the need for the 2 exhaust so that your pulling fresh air over your hoods.. however in a single hood all u need is a passive intake system.. intake holes at bottom.. carbon filter-hood-fan is all you need and the air being sucked out of the room by 440 cfm fan creates the negative pressure with appropiate size intakes to suck air into room through the intakes.. this has nothing do do with circulating fan.. yes u still need fan circulating in room

you place carbon filter at one end of room and intake hole on bottom of other end of room.. the exhaust sucks the airs through the hood as fresh air is being pulled in from bottom of room across the room to the exhaust. with circualting fan inside blowing on plants and moving air around.. only need to run seperate intake for lights is if your temps are running to hot or if your using c02 in which case you wld do what ur doing so you dont exhaust the c02

bluedreamzy said:

with 2 lights i could see the need for the 2 exhaust so that your pulling fresh air over your hoods.. however in a single hood all u need is a passive intake system.. intake holes at bottom.. carbon filter-hood-fan is all you need and the air being sucked out of the room by 440 cfm fan creates the negative pressure with appropiate size intakes to suck air into room through the intakes.. this has nothing do do with circulating fan.. yes u still need fan circulating in room

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He's 100% correct OP, go to Lowes or Home Depot or wherever and get yourself some nice oscillating fans. I got mine at Lowes for $19 each, grabbed two of them because they're fully stocked now that it isn't summer. I'm gonna go grab two more before summer hits and they're all gone! If you get that and a nice inline fan your plants will be loving you.