Which do you think gives off less heat, one 1000wt hps in a vertical, air cooled tube, or one 400wt hps+ one 400wt mh in a vertical air cooled tube? I'm running the two 400s and the heat is barely manageable (84-86 degrees F). Would i be better off with the 1000wt bulb? Buying a 600wt is not in...