just wanted to share this experience with you all. I bought a very small xenia frag 3 or 4 months back. it never displayed the pulsing behavior that I wanted. I thought maybe it was just small or maybe it just didn't want to do it. I upgraded my light from a current 40W pc to the 80W pc over 10g tank. I just witnessed my xenia pulsing. when I did I looked over at my wife with childhood amazement and said, "see, it was worth getting this new light that you thought I didn't need." I got the typical wife response that doesn't care for reefing at all. she just rolled her eyes and kept reading her magazine.