I'm going to be getting a used 200 gallon (7*2*2) and while it comes with MH's and VHO's I have always prefered t5's and plan to swap out the lights. My existing system is a 90 Oceanic with a 4*54 light and I have been happy with the results seeing steady growth and good colors. For the new 200 I am planning on getting 2 of the Icecap 660 retrofit kits with 4*39's so it will 4 bulbs deep by 6 feet across. Seeing that the Icecap ballast overdrives the bulbs, each will have an individual reflector and the tank itself will be about 1 inch shallower I believe I will actually see a substantial increase in light output. Does this sound good to everybody? advice, suggestions and wild ideas welcome