(03/16/2009) - What i like about these over full size LumenArcs and LumenMaxs is that you can hang them higher away from the water resulting in less splash on the bulbs and reflector, With the bulbs (400 watters) 12" from the water i get excellent spread over my 30" wide tank. I use (2) of these ofer my tank with 5ft x 2.5ft footprint. The Reflective material is excellent, extremely shiny and more facets than the aformentioned reflectors. Hope this helps.