i gotta say have learned alot oif info from this post...looks like i am going to need 5 400 watters over this tank so now i am deciding on what ballasts to get.. and yes dont want to leave m self limited but yet do like the 10k and 20k...just started looking over a new article and compaarison charts for sanjoy..maybe get a couple of each..

if you get 5 ballast replacement buls are gonna cost 0ver $500. Now is $$ is no big deal thats fine. But iwaski will blow thm away par wise. If you used regular ballast you can use 10-20-6.5 in a mix. If you went 2 6.5 and 3 20k you will get more than enough blue and mass par. this is if you want sps tank if not you may not even need iwaski. But fwiw Iwaski last 2yrs vs 1 yr 10-20k. it will help will bulb replacement cost.