Is a 200 cfm can fan enough?

I'm setting up a new space. A small closet 2' x 6' x 8' tall. I have currently set it up with flourescents and and a 200 cfm can fan with a charcoal filter. Works great as-is.

My question is: Can I add a 400watt HPS with a cooltube after the filter? Or would I need a larger fan? I have air intake from other rooms, so I wasn't going to pipe a new vent into the cooltube. I was going to go directly from the filter to the cooltube intake, then out the exhaust side.


I'm just not sure if the amount of air flow would be enough, through the cooltube. The filter already seems like it restricts the flow. On the other hand, even if I'm moving 100 cfm through the cooltube, it only holds less than a cubic foot and would seem like it could still work.

Any ideas/advice on this setup?

im not sure how much ur filter is restricting the airflow but i cant see any reason why u would have a heat problem if theres less than a cubic foot of air in the tube.
but i do know a way to test if ur fan has enough intake. get a piece of tissue paper and hold it to ur fan, if it holds then u got good airflow, if it falls get a new fan.

Do you mean hold it up to the filter? I've got one of the canister type charcoal filters, like a tube with intake all around 360 degrees.

yea that filter is a bit harder to test than holding something to a norm bathroom fan. i guess u go to the other end and test. if the out going air can move a piece of paper or something that u hold infront of it then u should be good, i mean with reasonable force and not some wimpy breeze. there might be a chart somewhere that lists what fans can go on certain wattage lights, or rather lights that need certain airflow.

Hey my 200cfm fan and I have a 4in x 20in filter works awesome with A 400w hps I got a zipper door I leave cracked about 6in at bottom for intake and. Been working for a year went threw two filters too

Try keeping negative air pressure when I zip my door shut it sucks in. Plants love the consistant air exchange

Perfect. Thanks guys; that's exactly what I was hoping to hear. Seems like a lot of people on here use 6" - 8" fans that are cranking 400 to 500 cfm, even for really small grows. I'm just wanting something that works without buying a lot of new stuff.