Hey Johneg I like your setup, I just ordered a coliseum, and I have been looking everywhere for someone who has used one. I think you are using 5 400W's Is there any heating issues in it. Im thinking about using 2 !000W's but I'm worried that there will be a heat problem. Also what kind of mix are you using? And how often do you water your plants. Do you know how much the yeild on a full 300 site growing plants 16 in tall. I think the recommened height is 1 ft plant but i dont know if thats right. I heard somewhere maybe an 1.5oz off each plant. If you could help me out by answering these questions I would greatly appreciate it.