i heard that its good to have a little bit more exhaust then intake air. but i also heard its better to have more intake than exhaust. any opinions? i have a 250 cfm and a 273. so i was just wondering which you guys thought would work better where. thanks

hi tpe,
if you have more vent than intake, then you will have a slight vacume inside your room. this is good because (this is the way i'm set up anyway) when the extraction fan is running there will be no smell around the grow room because it will all get sucked back into the room. it also means your fan will be working a little harder.

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noob 4 life

well that makes sense. do you have the vent and intake on the same side? or is your fan strong enough to bring it in from the other side?

I have ducting connectiong everything where i need it, but it is set up to pull the intake air across the room to my carbon filter. My fan (6inch Vortex) pulls air through the carbon filter, through my light, through the fan then outside.

f

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noob 4 life

oh i never thought of that. through a carbon filter through the light. so wait, is it light --> fan --> carbon filter --> outside? how many plants do you got going ?

carbon filter==>light==>fan==>outside

the fan is pulling air through the filter, then the light, then ..itself.. to the outside.
But you could put the fan on either side of the light i guess.

I have 5 pretty good size plants going under 1000w hps.

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noob 4 life

ohh i get it. thanks for the input man, you've given me some things to think about lol

alright so i got another question. do you think i need a cooltube and exhaust for a 400w hps/mh setup in a 3x3x6 growbox with those 273 and 250 fans i got?

tough to say... you kindof just need to road test it to see. you should get a thermometer that records the hi and lo temps and let the setup run for a day to see what kind of temps are happening in there.

cooltubes look nice, but there's a lot of diff. options for vented hoods.

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noob 4 life

I don't know about your fans, but your most likely gonna need to exhaust the heat somehow.

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noob 4 life