love my decision to stay with MH and t5 fixture. at moment I've been using 10k bulb with great growth on the new fixture, even with my old fixture that old bulbs I still saw great growth. just make sure you get a fixture with 4x t5 to get max color out your coral. maristar is releasing a new fixture $550 without ballast or bulbs but good reflectors. also love the lumenbright fixture, I hope to move to the one day.