Sounds like you need more exhaust not more in-take air, you should be running at least a 4" inline fan @ 160cfm+, I would run a 6" fan @ 400cfm and you will see temps in the 70's. Does the tent have vents in the bottom? Are they open? What kind of light hood are you using? Any pics of the set up? I run my tent with a negitive pressure, meaning that the sides of the tent are slighly sucked in from the amount of exhaust air that is venting out, I bring fresh air in by venting the bottom of the tent...pulling cool air in from the bottom and exhausting hot air out from the top, I also have a fan inside the tent to move air/plants arund. I assume you are only runnng the MH bulb now, need to remember that the HPS will run a bit hotter than the MH. I started with a tent your size, ran a 400w MH/HPS, with one 4" 160cfm exhaust fan, passive intake, and a fan side to move air and had no issues keeping temps in the lower 80's. You have to get the temps down below 90.....the better your temps are the easier and less issues you will have, less stress, less water, less nutes, healthier plants
Stlmatt
Stlmatt
Stlmatt