I ordered the Metal Halide lighting fixture from pet supply liquidators. I've wanted to try Metal Halide lighting but was concerned about the color. So I ordered a combination Power Compact and Metal Halide system for my upcoming 20 gallon tank. I've also wanted to try out the 55W 9325°K Super Daylight bulbs everyone has been talking about. I have read that Metal Halide bulbs shift in color after they are burned in. I am using the 70 watt Aqualine 5,000 German HQI double ended Metal Halide Bulb. I am really pleased with the color and it doesn't have a yellow tint like you would expect from a 5,000K bulb. I only have the 70 watt MH running on the 18T tank. The light is very natural compared to Power Compacts. The fish cast shadows on the substrate and the water refracts the light up onto the ceiling. The fixture is 12" from the surface of the water, and the evaporation rate is not to bad. The hangers make maintenance on the tank trouble-free.