In tight locations like that it would be better using CFL's than HPS.. Maybe you should change the HPS for a couple high-watt CFL's instead as they don't run hot at all (gets "warm" but far from "hot", can touch a 100w CFL without burning your fingers).
mahavatar Reviewed by mahavatar on . Heat Issue I have 400w hps in a 3x3x78 grow tent that's in the closet. I have a 500cfm fan blowing air out into the attic and yet I can't get the temperature down. With an added oscillating fan and without I couldn't get the temperature below 85 while the house temperature is 74. Any ideas? Rating: 5