This IceCap mogul base metal halide bulb offers excellent coloration and intensity. The crisp-white color will illuminate your tank nicely. Actinic supplementation may be used to create a bluer look. An electronic ballast, magnetic pulse-start ballastor magnetic HQI ballast is required to ignite these bulbs. It must also be housed inside a pendant. An excellent choice for nano-reefs and other reef tanks up to 18" deep. on how the different Kelvin ratings appear and more information on metal halide bulbs.