i remember reading something about someone that actually tested the suck vs. pull controversy... apparently that person found that sucking works a bit better. can't imagine by a whole lot though.
i'm running cooltubes... but i don't recommend them as i used to. i'd just go for a rectangular reflector with a glass enclosed bottom. Cooltubes are pretty crappy for light distribution. This is somewhat offset by the fact that they cool better than anything else so you can position the light as close as you want... but i'd rather have a better footprint under the light.
Cooltubes allow for maybe a decent 3 1/2' x 4 1/2' footprint while some of the others like the Magnum XXXL might give a nice 4 1/2' by 5 1/2' footprint. Though i don't have any personal experience with the Magnum.
To answer the Op's question though, generally you are pulling air from outside the room through ducting and putting it directly back outside again. But you could also draw air from the room itself and exhaust that out as a means of further improving air flow through the room. Ie; put a hole in the floor for passive air intake... and exhaust the cooltube with no intake ducting to an exhaust vent at the top of the room or through the ceiling.
Hi Gypsy
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