K so you have some venting issuses covered. Now a few things to ask and point out. Frist thing is ever think about doing a passive intake system for your ventilation? That might help to keep them temps steady cause it sounds like you just blowing hot air around. Now how many volts is your PC fans running off of? It might not be enough to pull all that hot air out. What are the temps when u have everything running? Is your MH air cooled? Also what genetics are you working with(