What the hell does a protien skimmer do, and how do you know if the one you have is sized correctly?, Same questions for wet/dry sump, I hear in order to keep soft corals you need stronger or different lights. Does this mean brighter white light, or different light?, At one time all my rock was purple several layers actually, however now its white, gray, red, etc... I've done nothing different. Thanks J. Velarde.