I have a 6 foot, 3 x 3 grow tent in my room. I'm using a 400 watt hps light and I have one fan with a flange to put on the tent. I was wondering if I should have it blow air into the tent or blow air out of the tent? What's more important? I also have a small fan that just sits inside the tent that blows the air to move it around. I had it set up to blow the air out but now my plants have what looks like calcium deficiency and I hear that it might actually be no fresh air coming in? I don't know what to do