Give your colorful corals a boost with the Zoo Med 420nm Actinic Coral Sun T8 Fluorescent Aquarium Bulb. This special bulb was designed to emulate natural blue coral reef lighting and recreate the chlorophyll-A absorption curve to improve photosynthesis. It also promotes the growth of essential zooxanthellae algae that’s vital to photosynthetic corals and invertebrates. Each bulb offers up to 10，000 hours of effective illumination and is great for use with marine aquariums， reef tanks and African Cichlids alike.