Saltwater Aquarium Lighting
Saltwater aquarium lighting is especially important if the aquarium contains corals. Lighting changes affect corals considerably. There are three primary categories of saltwater aquarium corals. The first category is the stony coral, which has an outside skeleton. The second category is the soft coral, which doesn’t have a skeleton based on calcium. The third category, SPS, is a small and short coral, which is stony and polyped. Lighting is crucial to saltwater aquariums that contain corals because no matter which type of coral, it needs photosynthesis for survival.The process of converting this saltwater aquarium lighting into food for the coral is just like the conversion by plants of sunlight into chlorophyll. There is another middle step to this marine life photosynthesis, however. Zooxanthellae algae actually consume the energy produced by the lighting and that results in byproducts that provide the corals with life sustaining energy.
What type of lighting and how much is needed are determined by the type of coral used in the saltwater aquarium.
The aforementioned zooxanthellae algae dictate the coloration of tissues and coral polyps. The differentiation of spectral output of the saltwater aquarium lighting can influence the shade and color of the tank’s corals. Changing from a 220 watt fluorescent aquarium lighting setup to a 10,000k 250 watt metal halide saltwater lamp can change the light frequency. This changes what all the aquarium’s marine animals have been accustomed to. What happens when the coral is startled in this way is that they shrink and close their polyps. What’s really going on is the recoil of symbiotic algae and this creates shockwaves within their host coral.
This isn’t the case for long, however. The algae and thus the coral adapt to this saltwater aquarium lighting change within hours or at the longest several days, changing their capability of light absorption, which changes the color of the coral.
The look of coral or aquarium creatures such as clams may well vary by where the owner or others peer into the tank. A top view may display beautiful colors, for example, while looking in from the side the same creatures or items will appear dull. This look is altered by the location of the algae on the particular animal or accessory in the tank.
The kindest way to treat the marine creatures in a saltwater aquarium to lighting change is gradually. The owner could change the burned out bulbs after the system shuts down for the night and, if there is more than one light, turn them on in gradual sequence. The reason is that, just like humans, fish and other marine creature don’t like to be startled by sudden light. Unlike humans, they can’t shield their eyes. Even changing one bulb for another of the same type and wattage is still startling because the old bulb had probably lost some of its luminescence, making the new saltwater aquarium lighting brighter than its marine life has become used to.
Metal halide lamps are the best type for SPS type aquarium corals. These corals are delicate to maintain and these lamps help keep that life preserving balance in check.