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[scarab]

SPS are light loving corals. Though different Genus and Species of SPS require different level of lighting, the general consensus is they need light, lots of it. If you are planning for a SPS tank, be prepared to spend a substantial amount on lighting.


Most preferred type of light is Metal Halide (MH) lamps. They are usually available in 150W, 250W and 400W although less popular configuration such as 175W is also available. If your tank is 2 feet in height (which is the most popular tank height), you will need to go for 250W or 400W if you want to keep SPS all the way to the sandbed or bottom of the tank. 150W lights may only allow you to keep SPS to about 1 foot depth. Light temperature will also plays a part in the choice. In general, low temperature light such as 6500K will give the best growth in the SPS as they generally have the best PAR value. However low temperature lamps tend to be very yellow in appearance which might be a turn off in terms of viewing pleasure. So a combination of lights, maybe with T5 (which will be discussed below), will compensate for the growth with the viewing pleasure. Other popular MH light temperatures are 10000K (most popular), 14000K(gaining popularity) and 20000K(more suitable for 400W due to the low PAR value). The higher the temperature, the light will appear bluer. Bulbs also comes in 2 types of end fixing, Double Ended (DE) and Single Ended (SE). These are as what they depict DE means fixed at both ends. Generally DE fires brighter than SE bulbs. The downside of DE bulbs are that they have no UV protective coat (SE bulbs have UV protective coat on the bulb surface), and they require an additional glass panel to cut out the UV from the DE bulbs. Ballast to drive the bulbs will also play a part in the final outlook of the light. Generally there are 2 types of ballast, magnetic and electronic ballasts, with the magnetic ballast tend to drive the bulbs harder, meaning brighter but on the downside will appear more yellow. However, this is not true for all the different brands of ballast. So choosing the right brand and type of ballast is also important.

T5 flourescent tubes are also gaining popularity as lighting choice for SPS. T5 comes in the following configurations, 2ft (24W), 3ft (39W), 4ft(54W) and 5ft(80W). If you are using T5 as your main lighting, would suggest that you go for at least the 4ft(54W) for optimum illumination for SPS. Also assuming a tank height of 2 feet, this configuration will allow you to keep SPS all the way to the bottom, although you will need to place some less light loving corals at the bottom. Placement of different Genus and Species of SPS will be dealt with in another section. Other flourescent tubes include the Very High Output (VHO) tubes. These are tubes that has a higher output per tube as compared to the T5.

Reflectors plays a big role in the efficiency of the light. Popular reflectors for MH bulbs are parabolic (normally in long pendant light fixture for both DE and SE), individual spider reflector (for SE) and the latest craze, the Lumenarc Reflectors (only for SE to date). T5 tubes normally uses long parablic reflectors caterred for individual tubes. There are some reefers that DIY one single large reflector on a few, say 4 or 6 tubes, where you can squeeze more tubes under one reflector. This will however be less efficient than the individual reflectors but will give you more option of different tube light spectrum as individual tube reflectors tend to take up a lot more space.

The above are just some general view and explanation of the lights requirement for SPS reefing. It is by no means exhaustive and further reading is encouraged. At least the above will give you a head start on what to look for and choices available. Lights are just but one part of successful SPS reefing. Please read the other parts of the write up for a more complete understanding of the SPS reefkeeping and husbandry.