Which type ballast are you running? Radium 20K's work best on a old M80 ballast. I run a M80 ballast, Sunlight Supply Bluewave, am currently running the XM 10K bulbs to try and get some nice growth, which I seem to be getting, but they say the M80's will shorten the life of the XM 10K's to like 6 mos. My corals are definately washing out some after a couple months. When the XM's loose their punch I will be putting in a fresh set of Radium 20K to get the color back.