My Grow box is 2 feet wide x 4 feet long x 6 feet high. (48 cubic feet) Will two 160 CFM fans, one for exhaust & one for intake be good for ventilating this space? If not what is recommended?
Isn't that way too much overkill? I will be doing a CFL grow, its my first one... I know about HPS & MH. BUT! I want as much air circulation as possible without overkilling it.
the question you ask is always a personal one.. it depends where you live and ambient air temp your bringing in to the grow space... all kinds of stuff its hot where i live, so i like to over kill with venting use a passive intake(more or less just a hole, but must be light trapped) and since i like to over kill with venting i like to exhaust grow space air three times in one minute... this means you take the 48 cubic feet and multiply times three... so just take the two PC fans and mount them for exhaust and cut two similar holes down low for the intake problem solved, as long as your not trying to jam more than 400 watts in there, but since your using pc fans my guess is this is a CFL grow(this also is greatly dependent on intake temp and size of light and cfm ratings of the pc fans) lots o variables
In my experience, Tihspeed has it right... - Run a passive (no fan) intake to create slight negative pressure in your grow space. - More air exchange is never hurts as long as you are not creating a hurricane for your plants...assuming you are not supplimenting co2, which I would guess you're not.. Good growing
I stated this is a CFL grow, and atleast don't think I said PC fans? Sorry If I was not so clear. I was thinking to just use in-line duct fans, 2, 1 intake, & 1 exhaust with carbon air filters on backs. My temps vary a lot where I live in my room where my box is. In winter not so much its right around room temp usually, give or take a couple of degrees F... Summer is a different story unless my parents put the air on (room temp - high 70's F) without the air and windows open its gotten up to 89 degrees F in my room usaually will stay 86 and under.
I was going to do my best to light/air proof my grow cabinet with weather stripping or something similar because its gotta be stealth. So a negative pressure intake is not really plausible.
hahahaha... don't ask if your not gonna listen... you need negative pressure to lock in the smell, or its gonna stink(good or bad however you look at it) the stink is gonna be so horrible your grow will loose its stealth... do what you like... MO, put both fans as exhaust and have the same sized holes as intakes... good luck... thanks ignorantfool for chiming in and the props
thanks? where did I say i'm using pc fans? Or is that your way of saying 2 PC fans will be fine, two 160 CFM in-linne duct fans are overkill. I'm trying to listen but you lost me. sorry.. I appreciate you trying I guess what I am trying to ask you is could I just have an intake fan instead of a hole? wouldn't that just really be much better in the long run(i.e. if I decide to get a 250w hps)? Perhaps the intake fan be of less CFM or half that of my exhaust fan's CFM?
160cfm is on the small side for duct fans...most people using fans that size use PC fans so that's probably where the thought can from...imo duct fans are better... One 160cfm fan should be sufficient if you are using cfls...if you want to use MH/HPS I would upgrade the fan to 240cfm or go with 2 160cfm fans... Just remember, when you put a carbon scrubber on you exhaust, you will lose airflow... Unless there is a specific reason why you want to run an intake fan, stick with a passive intake... If you have not purchased the fans, I would run a carbon scrubber and a 240cfm duct fan on the exhaust...if you fan is too big, you can slow it down...if it's too smal you're sol...
no... one fan, unless you like stink... even if you have two identical fans... power flux could cause stink to leak out of any crack out of the grow box, but if you have one fan, the stink can only go one place, threw your one fan and that should have some sort of filter on it or a ona bucket nearby I know logically this might not make sense but i would strongly encourage you to use google and look up negative pressures and why people use them with grow spaces, especially ones' where people don't want stink to leak out
Sorry I should have been more specific, two 160 CFM each in-line duct fans. Thanks I've got it down now with your posts and little more searching.
your absoulutely right it sounded like madness to me at first but I understand now, thanks and +rep for both of you