# lighting information



## Joey (May 27, 2009)

If you intend to keep corals in your tank, lighting is extremely important. I will admit that I have less than adequate lighting in my 72 gallon tank. I have 432 watts of a combination of Actinic 03 and Actinic White, which amounts to 7watts per gallon, the minimum required for a reef tank is 4wpg. 
It is possible to keep a reef tank with this type of lighting - just be aware that you are limited as to the species of coral that can be kept in your tank. Remember - if a coral is being kept under high lighting, it will not be happy with anything less. If you wish to keep all types of corals, you must install VHO or Metal Halide lighting. When purchasing a coral, be sure to discuss the type of lighting in your tank with the supplier to be sure it is adequate for the specimen you are purchasing. [URL="http://www.amazon.com/gp/product/0945738994?ie=UTF8&tag=jansree-20&link_code=as3&camp=211189&creative=373489&creativeASIN=0945738994"]A Practical Guide to Corals for the Reef Aquarium







[/URL] also provides an easy to understand chart system of required lighting for various coral species.
If I were to be starting from scratch, I would invest heavily in lighting, using a combination of VHO and Metal Halide. Next to water quality, lighting is the most important element in a successful reef aquarium.
If you plan to use Metal Halide lighting in your tank plan the fixture that will hold them accordingly - Metal Halide lights should be a minimum of 6" above the tank or they could burn delicate corals.
Lights should be left on for about 12 hours per day in order to supply corals with the amount of light they require. Some people use timers and dimmers to turn some of the bulbs on and off prior to the full lights coming on - this will simulate a sunrise/sunset period. 
Lighting can be a very complex issue involving the luminance and intensity of the bulbs used. Martin Moe provides an in-depth discussion of this in his book [URL="http://www.amazon.com/gp/product/0939960052?ie=UTF8&tag=jansree-20&link_code=as3&camp=211189&creative=373489&creativeASIN=0939960052"]The Marine Aquarium Reference: Systems and Invertebrates







[/URL]







. Basically, you want to use bulbs that are above 5500k and use enough of them to produce a minimum of 4 - 6 watts per gallon of lighting. I use two 20 watt Actinic 03 (rated at 8000k - a very blue light) and two 20 watt Actinic White (rated at 5600K).


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## MediaHound (Jul 19, 2006)

Very informative.


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## FishyFish (Jun 1, 2009)

Thanks! I'm new so guidance like this is really important. Are corals particularly finicky?


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