Aquactinics is supposed to be one of (if not the) best lighting fixtures available. From everything I've heard, about the only thing that beats them is a retro Icecap setup. Speaking of which, I'm not sure if they make it in the 72" variety, but the Solar Flare by Aquactinics looks to be the best of the best. It overdrives the bulbs with Icecap ballasts and uses Icecap reflectors.