my setup is similar to that one except the fan on the right is not there. I use a 1K hps in a 4'x4' hydro hut. The temps in there stay the same as ambient. I have a 6' vortex cooling the lamp. Also, there is a 4" vortex with a carbon filter for exhaust.

The first pic is the fan pushing air from left to right into the lamp hood.

The second is the exhaust, thats where the filter hooks up. Eventually it goes to the attic. You can also see the vent on the other side of the light. That goes to the attic as well.