I figured if the roots were cooler than the air around the plant its ok but if the roots get too warm then the plant starts to wilt..I did move the vent fan lower..right infront of the water resevoir to keep the water cooler and it seems to work. The 400 hps is bad ass, its actually cooler than the 2-150's. A lot more weight too from the 400. still 83 F inside...peace