Quote Originally Posted by littlemountain
purchasing gear for my first grow-room- need advice on exhaust fan- room will be 640sq feet-6" exhaust duct...
Assuming you mean *cubic* feet. That's a decent size space. Depending on your lighting choices, and if you vent the lights with the exhaust, you may find that a single 6" vent is on the ragged edge. I'd probably be looking at a good 8" or 10" inline as a minimum. I like both the Vortex and Sunleaves fans personally, with the Sunleaves seemingly being a little quieter. Running with a 6" it'll have to run at full-bore if your venting HID, it won't be very quiet.