I have a 20 gallon reef ish, no coral as of now, and when I picked up some a few months ago it basically just died. There were many problems with my tank back then, most of them solved to date, and I am still scared to get any coral at all, so if I do get them, how should I feed basic stuff like gsp zoas ect. And also, what do I dose, when do I dose, and why do I need to dose if I do need to.