[Aquattro]

Originally Posted by Bryan

There is a lot more to color and growth than lighting, e.g. alkalinity, water movement, DOC etc..

I snipped this from a thread on RC because I thought it really explained everything about coral color...reprinted without permission, but hoping nobody minds...

"there are only two things which affect sps coloration. These are zooxanthellae density and accessory pigments.
Accessory pigments are determined by growth, light intensity and spectrum.
growth is also determined by calcium availability, alkalinity, trace elements, flow, temperature, salinity, food and stability. zooxanthellae density is relative to nutrients, growth, temperature and light intensity, spectrum and duration.

when corals exhibit fast growth, the growing margin has fewer zooxanthellae and more accessory pigments leading to colorful tips or rims.
Zooxanthellae can mask colorful pigments when they are in high densities. In nutrient poor conditions and under high light intensity and ideal spectrum, zooxanthellae populations will be further reduced leading to more visible accessory pigments especially within the body of the colony.

As you can see already it is a very complicated and weakly understood process and I am sure I have left something out.


__________________
Jake Adams"