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the amount and type of lighting will be directly related to what you intend to keep. For teh most part, 5watts/gal
lighting is plenty to keep a wide variety of soft corals and LPS
corals. The watt/gal
rule is really more of a very general guideline and I do not depend on it mcuh at all. It is much better to decide what you wish to keep and build a system around that. SPS
corals, clams and some anemones require more intense light so MH
is a better choice for these. If you can narrow things down a bit we can offer a bit more detailed advice.