Quote Originally Posted by PharmaCan
Al - you make a good point about the air pressure. I'm using the cooltube to exhaust the cabinet w/ fresh, air-conditioned air coming from inside my house. Since this is a veg cab, I wasn't worried too much about the smell. However, I am using a big exhaust filter.
Yep, you're quite right, vegging plants don't stink much. Your filter may not be needed, but soon as you removed it, some nosey-nose would pick it up.

My cooltubes are for a pair of 1000s in a flowering area. They are getting a completely independent air circuit- cool 'clean' air in from outside the op airmass, pressurised tubes with blowers upstream, dumping air also outside the op airmass of course. No filtration needed as I'm not drawing 'stinky' air through the circuit.