I have two fans in the room. I also keep the door open when the lights on. at least until i can get a squirl cage and a air scrubber and a lot of other stuff just dont have the money yet. I need to also get a ppm meter. Never tested it. just my PH which is always around 6.0. How much is the avage amout of bud you get off a 400 watt HPS light? Your grow looks nice wish I had that much room. where did you get your WW seeds? I could use a good hook up!!!