Corals including sps are ferocious eater. They do not get full and then stop eating. They will eat as much as we give them, if they (the zoanth algae) get more than they need they pass it on to the coral calcium carbonate structure. or excrete it back into the water. So the answer is yes feeding sps is important. Here is the catch 22! If phosphates rise to high above NSW levels our sps turn brown. So the question is how do we feed without letting po4 rise. Every system is different in its ability to process nutrients, depending on skimmer size, chaeto, gfo, etc. So the key is to feed only as much as your system can digest because overfeeding will brown out corals due to high po4. Fish food, coral powder foods, and other stuff we put in our system have both no3 and po4. So regular feeding and in turn fish poop raise po4. So in a system with elevated no3 and po4, we need to reduce feeding. If our sps tank has .02 no3 and no4 then feed until yo find the point of equilibrium where feed and digestion match without raising po4. Now another twist----Dr Redfields ratio! This says our corals, algae,bacteria will consume more no3 than po4 by some number between 10-20 times. The exact number is something for scientist to argue about. The key point is our system may go no3 deficient or limited or starve corals,algae and bacteria of the nitrate they need to make protein and grow. So the answer in this case is to feed a nitrate without a po4. This is what a good amino acid like MEamino will do. Raise no3 which was deficient as a food source without raising po4. Aminos are a pure protein that corals have been shown to absorb quickly from the water column and it will increase growth and coloration in a low nutrient system.
PS Someone mentioned live food like phyto------The key here is live food does not die so it does not turn into po4 and no3 that neeeds to be digested out. And is the best food. I love live rotifers!
