The first is a 5x5 room. 8" fan pulls air out of the room via the 2 open ended hoods. Exhausts into the attic. Fresh air is blown into the room via oscillating fans. There is so much air being pulled out that havent needed an active inline intake yet. Those are 2 600 watt digitals.

Second is a 4x3 room with a 1000 watt cool tube. Pic is a little old, the y-pipe was removed so all air is pulled through the cool tube instead of part of it. It is staying cooler because of this. You can literally touch the glass even after the lights been on all day. The room is fed by a slower 4" squirrel cage. A 6" inline fan pulling air from the 4x3 room would drop temp another 5 degrees for sure. And humidity.