I have a 2'Wx4'Lx8"H shower stall I have been trying to grow in with minimal success. The plants seem to just stop after a couple weeks and then die. I just received some great seeds and need advice before I try again. I have a 400 watt MH/HPS light and a small fan, and am using a growbox with good drainage. I think it is the growbox, as I seem to get lots of little "houseplant" flies even with minimal watering and misting. Any and all help would be appreciated.