Hello
Let me try to answer some of the questions. First I do believe its best to dose just before light out. Most corals feed more at night; however as reefers we want to see our corals eat(human pleasure). So I suggest adding aminos 15-20 minutes before you feed your fish in the evening. Two reasons. First the aminos (some) produce a feeding response in 15 min, so while they are feeding why not give them the same food you give your fish also. Food that may only be available for a few minutes before the fish get most of it. Second the aminos will then still be in the water column in the evening to feed those that did not want to feed in the daytime.
The other question related to brand. I think whats important here is that we read the labels. Aspartic and glutumic acid are the most important to corals. Some amino products are actually all in one products with vitamins,trace metals, carbohydrates etc. Anything that makes the bottle seem more valuable? Some of these other things can add phosphates, which can produce cyano and other unwanted stuff. So look for a pure product that is willing to disclose ingredients. Hope this helps
