Hey guys, first time grower here I have a 3'3/4"(w) X 4(l) X 7(h) grow room that I am using, it's perfect size but the problem is... NO ventalation. I have the walls covered with mylar and I am running a 400w MH right now. I don't want to pay the big money for the water cooling system and there is no way I can duct cool air into the room. I need some alternative method to cool the room (closet). Anyone have any ideas?