What k is your 150s, and how far above the water.Reason for asking is I have3 rbtas in a 20L with 2 150 hqi 14ks 13'' above the water and they are loseing their color. They are fed 2x a week silversides and krill soaked in selcon.I also do 20% water changes ever week, skimmer 24/7 and run carbon 24/7.My xenia are growing like crazy.Just hopeing you might have a clue to what is going on with mine. btw your tank is really nice.I will shut up now Thanks david