- 1). Determine what types of organisms will be kept in your tank; fish alone require far less intense lighting than a full-blown live coral set up, but almost all saltwater tank keepers will at least require some sort of saltwater-rated fluorescent lighting to provide the adequate spectrum for healthy microorganisms and zooxanthellae.
- 2). Find out what spectrum and intensity of lighting will provide optimal growth for the plant and fish life you would like in your reef tank. Corals, for instance, will generally require light in the 420 nanometer range, or the "blue" portion of the spectrum. As such, actinic bulbs and coral bulbs have been developed to provide the best spectrum of growth for reefs, but intensity requirements will vary by species. A good average to consider is between three and five watts per gallon for most corals and live rock.
- 3). Decide on a type of fixture that both satisfies the intensity requirements needed for your aquatic life, and fits over your tank. Metal halides and VHO (very high output) fluorescent tubes, such as T5 VHOs, provide the most wattage and intensity compared to size, so are good selections for both small tanks and tanks where very high light output is needed.
- 4). Determine a realistic budget for your lighting system, and select a fixture from a reliable manufacturer with good reviews. Reef lighting can be very expensive, but the old adage about "getting what you pay for" is exceptionally true here. Cheaply made fixtures can cause bulbs to burn out prematurely, or even short out altogether. Even worse, low-end reef lights have been known to cause severe electrical shocks to both fish keepers.
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