So I got everything all set up and currently running trials with temps and humidity and all the like. Right now Im using a 4(l) x 2(w) x 5 (h) tent. 600w cool tube (Ipower ballast) and Ipower filter and inline fan. The fan is supposed to have 430cfm. I have the carbon filter inline with the cooltube. It doesn't seem to sucking much even though I don't have much ducting throughout the entire system. However, the tent is being sucked inward... which I think is funny. My temp on the ground seems to hold at 73 degrees. The distance from bottom of hood to ground is 39.75 inches. The humidity stayed in the ok range. With the thermometer about a foot away from the bottom of the hood the temp is 86 degrees. With the humidity at 27 percent. I haven't checked temps with everything off but Im sure it should stay pretty warm and not get too cold with lights off. Im sure if did get too cold I could just throw one of my old heat lamps in when lights are off. They produce no light just heat. Excellent for reptiles.