If you guys would talk to Dana Riddle, he would explain to you about non-photosynthetic reflective proteins being responsible for our bright oranges and deep blues, when color is the variant in coral.
There is much current research on the additions of Amino Acids, vitamins, lipids, and protein supplements to help promote invertebrate growth.
All are safe when dosed properly.
I dose 2 500mg capsules of Amino Acids daily. Filter feeders and sponge growth is phenomenal.
I dose 1ml dry 100% whey protein(unflavored) to 5 ml seawater and apply with syringe. Filter off. Wait 20min. then turn back on. Anymore than this dose will cause the skimmer to go crazy and wet foam for a long time requiring a water change to chill out the skimmer.
I use Vita-chem 5 ml per day liquid vitamin supplement daily.
My zoas/palys/softs look great. My SPS grows quickly, especially my Sunset montis.
I got a nice piece of Leng Sy Monti and dipped it too long. It lost all of it's zooxanthellae and only a dozen or so polyps were visible on the skeleton. There are 5 people who have seen the white skeleton with light green polyps who are all amazed that the coral has fully healed. Vitamins/proteins is the only reason for recovery.
I feed a ton of flake food to my corals. Yes, flake food. I grind it to a powder, then mix with water, then add the powdery water to the tank at night. Polyp capture is amazing. Corals are extremely healthy, robust, and growing. The only problem is keeping phosphates lower than .01ppm. Therefore, my SPS acros turn brown, but still have great color on the tips and grow very well. If I drop the phosphates, the corals will color back up.
Any over supplementation will quickly be removed by the skimmer and activated carbon. That is why turning off the filter for close to 30min a day will help the animals feed.
HTH, Rich