Okay, so there are 2 70 watt hps's in there. The heat that they produce isn't too bad, but the magnetic ballasts associated with those are pretty hot items. I'm going for ultimate stealth so if at all possible, I would like to eliminate the need for cooling. The only idea I have so far is to place the ballasts in a small tub of mineral oil for liquid cooling. Currently the cab is in a temporary set up buried in the back of my closet. The ballasts are on top of the cabinet, on the outside, so they are not contributing to the heat inside the cab. The top vent is also not on, and I have a fan blowing in the front of the grow area. I already have a piece of glass cut in between the light chamber and growing chamber. The inside of the grow chamber reads about 88-89 degrees farenheit. But the closet itself, I think because of the ballasts, is about 140 degrees. I'm not too concerned for light penitration as the inside of the box is so small, I'm going to do small plants and a hella lot of lst. Or a micro SOG, I can fit 2 rows of 4 party cups max in there. If I can eliminate the space needed for the lights, ballasts, and cooling components, I can focus more space to odor control. With how it's set up now, there's not much space in there for that.