2.) suck air in carbon fitler -> 6" vortex -> out the window
suck room cool air -> 6" vortex -> 2k watt -> out the window

I'd go with plan 2.) but use an 8" for the cooltubes. I use a 6" for a 400w and it could cool two but for 2 1000w I'd feel a little better with a bigger one. If you dont need all the power or want to quiet it down some, get one of those speed controllers for fans.

At one time I considered doing what you planned in 1.) but several of the people here thought it was not a good idea to draw through the carbon filter first, then over the lights so I ended up with two fans.
doco Reviewed by doco on . CFM backpressure i was reading this on another thread fans are tested without ducting which give them the cfm. The thread also mention that if you use ducting, it will cut the cfm by half. No one on that thread asked if it will cut more than half if ducting and carbon filter is use. It got me thinking since i just upgraded and i need a fan that will cool 2000watt in a 64 cubic feet room. Any input on this would be great. thanks in advance Rating: 5