I originally upgraded to the Radion XR15W. I wanted to buy corals so I just bought one at the time. So now it has come time for me to purchase the second fixture. While I was online about to order it, I took a look at the T5 fixtures which were basically the same price as one fixture but can cover the full 36in length. So I am thinking about switching to a 6 bulb ATI sunpower 36in T5 fixture. The question is: Who here uses t5 and what is your bulb configuration?