There is no direct relationship between amino acids and color as far as I know. Where did you hear that?
To illustrate Gary's point, the extra nitrogen some of which will go to nitrate as the amminos breaks down , will more likely lead to coral browning as it drives zooxanthelae growth( all zooxanthelae is brown) sometimes to levels that produce oxygen radicals that harm the coral.
As noted, skimming will remove some of them as most are amphipathic( charged one way on one end and the opposite on another) and readily trapped in the air water interface between the bubbles.
In my opinion ,all in all they don't have much to do with color but can be useful in anemic tanks with over reduced nutrients,not a likely ocurrence unless you don't feed, keep fish and use heavy organic carbon dosing .
Clear water, the right lighting ,flow , very stable in range parameters( salinity, temperature, ph, alkalinity,calcium, magnesium, etc) , nutreint management,proper feeding and regular water changes do very well by color and health . Just adding ammino acids without a specific purpose simply adds more crap to what might be an already foul tasting mulligan stew but it sounds cool and will lighten your wallet .
