Light Coral

Is it necessary to have a “power compact” light in order to grow coral in a saltwater tank?

Power compact light? First off you need to know what kind of coral vs. lighting type.

When it comes to how corals grow, each category of animal requires its own unique lighting requirements, but all share one common trait; photosynthesis in order to survive.

Just as plants convert sunlight to produce chlorophyl, marine animals survive similarily by converting light energy into “food”. Actually, this energy is consumed by zooxanthellae algaes that produce by products that the corals need to survive; a true symbiotic relationship.

Coloration of coral polyps and tissues is dictated by these zooxanthellae. By differing the spectral output of our tank lighting we can actually influence the ultimate color/shading of our corals. How? Let’s say that we have been using a 5500K VHO flourescent setup at 220 watts. We get that itch to spend money and help our tank and animals by installing a 250 watt metal halide with a 10,000K lamp. Aside from the asthetics of the rippling light show these lamps provide, we have suddenly changed the frequency of light that all the animals in our system have grown accustomed to. I use the term “frequency” to describe the change in CRI or spectral output.
Often, the corals will shrink up, close their polyps, or otherwise show their displeasure at this sudden and drastic change in their energy source.

It’s actually the billions of symbiotoc algaes that are recoiling, sending shockwaves through their host and causing this rapid change in appearance. Within days, and sometimes even hours, the zooxanthellaes will adapt to this new frequency and intensity by changing their absorption capabilities or their overall color. That’s right, the coral’s color is actually that of their hitch-hiking algaes, adapting to the increases or decreases of ultraviolet and other energy-source factors.
SPS (Short/Small Polyped Stony) corals are by far the most numerous in the skeleton catagory. I will not delve into the physiology or other biological factors of these corals, other than to state that they, above all others, require the most dynamic of light sources.
Not until the advent of aquarium related halide lamps was this light source truly ready for our use. The incredible intensity of the metal halide lamp ( which is really what I think you are meaning here) makes providing the right output of light ideal for maintaining these delicate-to-establish corals. Once they grab hold, SPS corals can be the most proflific of all their kind, growing at enormous rates and prompting many cuttings. These coral cuttings, known as frags, can then be propagated through “coral-farming”, which is highly practiced by many hobbyists and commerical aquaculturing companies today

Naturally, factors other than the lights themselves contribute to the success of any coral, but once the water parameters and the lighting system are acceptable to the animals themselves, watch out. LOL!

QisDesign-The Birth of Coral Reef LED Table Light (English)