cool air in the bottom hot air out the top, realy no need for the cool tube IMO just have good air flow,, I veg. in this box and have flowered in it also with a 400W hps m,,did just fine.:hump:
IMO buy the cheap lamps & replace often, I have used high dollar lamps, some folks love them, I don't think there worth the $ IMO. but I only use CFLs, 1000W hps, 400W hps and 400W MH in my grows
if your just starting out use some cfls to veg and a small HPS like a 250w to flower with. you can get great bud with that, if your new to growing just on not killing them first and quality will follow