When it comes to coral color, aquarists often focus on two factors: zooxanthellae and florescent proteins. The zooxanthellae (zoox) which is a symbiotic organism living within the corals (zoo-: animal, xanthe: yellow). Like the name suggest, zoox are yellow in color. They live within the tissue of coral, grow and multiple based on the availble inorganic nutrients. Coral derives nutrients from zoox, and in turn provide refuge and inorganic nutrients to support their photosynthesis.
Since zoox is yellow, its concentration will directly contribute to the golden/yellow c