The 50/50 Fluorescent Lamp is a mixure of 50% 10,000K natural daylight and 50% True Actinic 03 Blue phosphors. This full-spectrum lamp provides tank inhabitants with the proper light required for esssential biochemical reactions. Organisms dependent on light for photosynthesis will thrive in this lighting environment. 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.