Damn I meant flower not veg in the post two above. I've been growing with a 600W HPS, has worked well but the bulb is getting old. I'm torn between getting two new 600W HPS in a 4' long cooling tube or a new 600W HPS with a 400W MH in a Growzilla (enclosed reflector 21"x21", exhausted). What would be the different benefits of either setup, or what do you think of either option. My friend thinks the two 600W is the way to go. Thanks