Add to it and make your reef happy!
Not just used for viewing the aquarium, high quality lighting is an important part of equipment for a marine or reef aquarium as it helps bring out the vibrant colors in fish and is used by most coral and some invertebrates as a food source.
T-5 Florescent lighting is a widely used system by both novices and experts alike. Normally offered in complete two, four, and six bulbs fixtures, the two and four bulb systems are perfect for fish only aquariums, where as six bulb systems, having a higher out-put can normally provide enough light for many types of coral. These systems stay rather cool, mount directly on top of the aquarium, and have a large variety of bulbs and colors to choose from that require to be changed every 9-16 months.
Metal Halide lighting is an older technology, but still preferred by many coral keepers for their higher out-put that's sufficient for any type of coral and especially useful in deeper tanks. Normally offered as a retro-fit system that require one or more ballast, socket, reflector, and bulb, that can then be hung or mounted directly to almost any canopy. Bulbs are commonly offered in three to four colors (temps) that require to be changed every 9-12 months and may be supplemented with florescent or LED lighting for extra coloration and some added “pop”. One thing to consider though is that this type of lighting does get hot, so adequate cooling should be provided.
LED lighting is new and easily the most versatile type of light available. Each systems' installation varies, with most either hung or mounted with rails. All are extremely energy efficient, stay cool, and almost never need to be changed. And with most fixtures capable of adjusting intensity and programmable settings, lighting can be turned down for a fish only aquarium or dialed up for a coral filled reef and set to create that perfect shade of color.