Just some confusing with the amount of fans needed

Lets say you have the standard 10x10x8 room for growing. 2 1000's in it. theres a window on one side, a door on the other. would you need a 400-500cfm inline fan to suck all the air out of the aircooled hoods and out the window, and another maybe 800cfm fan hooked up to a bigass carbon filter pushing the air in the room out the window as well or what?

Don't really need the 800cfm fan, two 450cfm would do the job. You would want push air through the hoods and pull air through the filter and out the window.

I'm still a bit confused. I've been under the impression that you use an inline fan to suck air through a hood, through a duct and outdoors. I thought blowing air through a high temperature hood was a bad idea, don't really remember why, I just remember reading it somewhere. Aren't you supposed to have one vent open so it pulls air through the hood and outside?

Also, hows the carbon filter work? I've been thinking you hook up an inline fan to suck air out of the room, and through the carbon filter. Then you vent it outdoors? How does that eliminate odor if all the stanky air is just being filtered and pushed outside?

Sorry bout bein a newb, but thanks for you help =]

Anyone think they can help clarify it up please? I've been looking to make purchases today but I haven't been able to get around to it as I've been seeking enlightenment from ye fellow growers

still a newb myself mate but (someone tell me if i am wrong) basically if your room is air tight and you have your carbon filter inside the grow room with your fans sucking air through it (filtering the smells) and then throwing that clean air outside then that is the only air let out of the room and it is clean.
with the cooltube your just circulating cool air from outside past your bulbs and outside.

hope that helps but in terms of room size and fans required there are loads of forums explaining how to work it out mate.

this is pretty similar to my setup here, i did this real quick in paint just as example....

the only thing i dont do is push my air outside, i made a hole and push it to the room next door, and for the inlet i made a hole into the bathroom and let it suck in frsh air from the window in there...

i dont push it outside because i'm afraid it will give off heat or alarm neighbors, but if that not a problem for you then it shouldnt be a big deal.






i wanted to add that i only have the glass under the hood in one of them(the one closest to the fan sucking air out) and the other one has no glass.


i also have oscillating fans on at all times.
one on the lower canopy and stem area, and another on the upper canopy and space between the trees and the lights.

Thank you thats very helpful. But why is the hole sealed? Where does the air for the fan to move come from in if all the hoods are sealed? I guess theres an exception in your case because you dont have the glass.

So you use the same fan for the carbon filter as you use to ventilate your hoods? Is that a good idea for a large ( 2-3 1000w lights) grow in a room like that? It seems logical to me to just have the carbon filter recirculating in its own room, no? And if you have an intake fan somehwere bringing in fresh co2 it should be good, but 'm not sure if that would work

Zarezhu said:

Thank you thats very helpful. But why is the hole sealed? Where does the air for the fan to move come from in if all the hoods are sealed? I guess theres an exception in your case because you dont have the glass.


i have the last hole sealed so hot air from the bulb doesnt escape that way and only moves thru the ducting.
if i had the glass on both hoods i wouldnt seal the last hole.

i just took the glass off one because it decreases the span of light it puts out by like 2 or 3%



So you use the same fan for the carbon filter as you use to ventilate your hoods? Is that a good idea for a large ( 2-3 1000w lights) grow in a room like that? It seems logical to me to just have the carbon filter recirculating in its own room, no? And if you have an intake fan somehwere bringing in fresh co2 it should be good, but 'm not sure if that would work

Click to expand...

if your room is completely sealed than it shouldnt be a problem. the only time you will smell the dank is when you step in the room.

heres the thing, if you are venting out the window with no filter you are putting stinky air into the atmosphere for your neighbors or whoever walks by to smell.

if you have it recirculating in its own room its sucking smelly air in and pushing it back out into smelly air, i guess if you had a strong enough fan it wouldnt matter, but i would rather go for the safety of knowing that air leaving that room is for sure clean.

Extremely helpful, +rep, thanks
gotta love rollitup haha

in that sketch... the fan in in front of the carbon filter.... but i've always read you should suck air through the filter in stead of blowing it through