venting from inside a grow room

This is my first post, and i have done a lot of reading. With that in mind here it goes.

I have a grow room that is 2ftx4ftx8 ft in a . The room is splt in 2, 5.5ft for the top (flowering with a 600w hps) and 2.5ft for the bottom (vegging and seedlings with 6400k CFLs). I have cut a hole in the bottom (left side) section which is 4" ( all holes are the same size) for passive intake, then on the opposite side (right side) a hole cut between the levels connecting the rooms (used a zig zag divider to keep the light out but allow the air flow). Lastly a hole at the very top left venting to the attic. In this hole I have placed a duct booster fan to pull the air through the holes. I am still running too hot with the lights on (104°f).

So the question is this. How can I fix this? If I attach a duct to the lights hood thus drawing the air through the bottom section into the top section then through the light then the attached duct, will that help? Or should I get a vortex inline(6") ? Can you draw air from the grow space through the light hood? Or should I cut a second hole attach ducting from it through the light hood, then meet with a y joiner for exit (again would I be better with the booster or a inline vortex?)?


I know generally the answer is bigger = better, but I'm working on a tight budget and $240 is a lot for an inline fan.

Its that booster fan, its not a venting fan so there is your problem.

You will need a 6" fan, and if you have 240 to spend, then you will have most of that left if you buy smart and don't fall for some hype.

Steal on ebay, hydrofarm 6" brand new shipped to your door for 75 bucks (not my auction just one I searched up for you). I have the exact same one, it's been running non-stop for 4 years now. And I mean literally non-stop, other than a few power outages over the years, it's never off. And get this, I bought it used on craigslist. Who knows how old it is, lol. Its more quiet than my other inline fan from htg, and the green fits nicely in a garden

http://www.ebay.com/itm/New-HYDROFA...Inch-In-Line-Fan-400-CFM-Blower-/390582965771

It's on sale, so you better move on it if you want it at that price. Fuck, I might buy one simply because at that price I cant beat it and eventually I'll need another......

Have you tried a straight through setup but like spandy said, you will need a decent extractor. Pull clean cool air from outside your tent, over your bulbs then straight out. As this air will be clean I would suggest pumping it into your house / flat to keep the ambient loft temp as low as possible.

you can use your booster to vent out of the top of you flower chamber. If you straight through extractor is efficient enough the booster fan should be fine, I don't see a scrubber anywhere, dodgey matey, smell control is rule 1 for going undetected.