Be confident in your purchase we're an Authorized ATI Dealer. How cool is that?!?!? ATI has been some of the most sought after bulbs in the reef aquarium hobby. With their bright crisp colors, ATI are our number one choice when it comes to T5 bulbs. With ATI bulbs you can use a single color on its own or you can mix and match to make the ultimate spectrum. The Blue Plus bulb is by the hottest selling T5 bulb available, for its crisp blue, that brings out awesome coloration in corals. : ATI has been some of the most sought-after bulbs in the reef aquarium hobby. With their bright crisp colors, ATI are our number one choice when it comes to T5 bulbs. With ATI bulbs you can use a single color on its own or you can mix and match to make the ultimate spectrum. The ATI Blue Plus T5 HO fluorescent bulb combines the properties of a blue bulb with a True Actinic Blue 03 bulb. Encourages bluing in SPS corals and fluorescence in capable corals. Helps balance out a washed out or yellow hued tank. Works well as a supplement to metal halides or in combination with a 6500K ATI Sun Pro or an ATI AquaBlue Special.