The 10,000K is purified super daylight lamp that simulates the high-intensity lumen output of the midday tropical sun. It contains rare-earth color enhancing phosphors to emit sparkling, blue-white rays. Compact fluorescent lamps emits powerful lumen output without consuming high energy or producing excessive heat. They provide photo-biological light requirements for aquatic life and enhance the appearance of the aquarium. The lamps come in two styles: European straight pin base arrangement and japanese square pine base arrangement.