i just joined the forum although ive been lurking here for awhile. im running into some extra annoying problems this cycle and could really use some advice on lighting and ventilation. here's my situation my box is 27" deep, 6' wide and 6' tall. i was running one 400w switchable mh/hps in a ventilated hood. the cfm of my fan is unknown. appliance tech here that used a microwave exhaust fan. with a well sealed box it was creating enough neg pressure to make opening the door quite a bit harder. this cycle i wanted to try scrogging so i bought a second(basically) identical ballast and rigged a hood to be air cooled. when you're on a budget... i got a splitter and am ventilating both hoods with the one fan. since my diy air cooled hood didnt leave enough room for a mh bulb i am vegging with both hps. i have some fresh air intake though it could certainly be improved on. now with all that said... my problem here is(you guessed it) temps are up there and growth is slow! the temp with the door shut is 85-86 even a little higher sometimes. i have my thermometer probe near the top of the plant out of direct light. by leaving the door hanging several inches open, leaving my window open(not the fresh air intake btw), and freezing my a$$ off i can get the temp to like 78 but thats not goingg to work for long and summers just getting warmed up. even a 5000 btu ac unit is more juice than i want to run, so i don't like that option. a swamp cooler adds more humidity and takes up valuable realestate, and with the door open the air flow through my outside exhaust is getting noticeable. my goal here is stealth and that vent is 2' off the ground 7' from my backdoor. not good. a bigger fan will only make that worse, unless maybe a muffler or reworking the faceplate of the exhaust will quiet things down? the only thing i can think of is getting more effecient hoods like cooltubes or what about switching to one 600w on a light rail mover? anything i havent considered? my walls are lined with foil shiny side out btw. how much could that be raising the temps? my lights are 12" or so from the tips and i have a large fan circulating air down by the plants.