What size intake and outtake fans

hey there, room is 6FT x 7ft x 7ft tall, so almost 300 cubic feet of space. How much fresh air do I need to bring in per hour or per day. I seem to have read on here that the intake fan needs to be half what the extraction is. Thanks.

You need like 1 complete exchange of air every 2 minute to replace co2 plants. Maybe a little faster to keeps temps in range. Just keep in mind that installing duct and filters will have a pretty big impact on much air fan moves. And the temp of intake air may need you to move more or less to maintain proper canopy temps.

Also, if you’re using filter in tent you want to maintain negative pressure inside the tent for scent control. That’s why you see suggested smaller fan for intake than exhaust. I would say get both fans with good speed control so you can dial in what you need.


Thank you, not going to use a filter, will send the exhaust to the great wide open. So looks like I need something around 9,000 SCFH.

That doesn’t seem right. A 600cfm fan with no restrictions would exhaust a 300 ft³ space twice per minute.

I’m just an idiot at times, so more like a 150 SCFM fan ? hope this right.

Check out the 6 inch infinity on Amazon, come with temp and humidity control. I run that as my exhaust, and have one 6 inch from outside , and one 6 inch from my garage intake vents


Thank you Tinman

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Good morning, so I can buy two of these and use one for intake and one for exhaust ?

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I run 2 of the T6 ac infinity fans and they are great. If you went with those you will be really happy with the results.


I only use 1 ,as a exhaust. The air will get pulled in through the intake, exhaust the hot air out at the top of room/tent , pull fresh air in opposite side room/tent at bottom


Thanks Tinman, are you using a separate intake fan to pull fresh air into the room or just a vent built into the wall. Also thanks for the info on where to exhaust. Just thinking about the intake, would say a 12”x12” or a 16”x 16” grill at the bottom of the door work?

No intake fan

i used two 6x12x6 strait boot with sidewall registers, i can close the one from outside if its to hot or cold out

If you buy the one with the control it comes with a probe, i have the probe hanging at canopy height

Thanks so much Tinman, this clears up my exhaust and ventilation. Took me a few to figure out the purple things, that’s a great idea. Now I can order the fan, do my cutouts on my walls and stand them up and get to work on this. This has had me in a holding pattern for the last two weeks. I have my light pick out and have my wiring figure out, time to get to work. Thanks again.

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No problem, good luck