I have the same exact fixture and just put in four URI bulbs, two super actinic and two actinic white, All corals seem to love the new bulbs and lighting. People may not agree, but i even have a clam under these lights, although higher up in the tank.
_________
Equipment: 55 gal, Remora Skimmer w/ maxi jet 1200 pump, 4x54w T5 lighting, 2 super actinics, 2 12,000K actinic white bulbs, 55+ lbs fiji live rock... Inhabitants: Ocellaris Clownfish, Yellow Tailed Damsel, Six Line Wrasse, Yellow Watchman Goby, 3 Chromis, Crocea Clam, Skunk Cleaner Shrimp Corals: Zoas, Yellow Fiji Leather, Pineapple Brain, Frogspawn, Pearl Bubble, Blastomussa Merleti, Monti, GSP, Green Psammacora |