hi, i have a 72 g bow, 2x150 mh, 2x28 actinics, sump with carbon bag, phosban reactor, MTC skimmer....my question is..do i need bio balls in the sump or can my live rock in the tank be enough?? currently have lps, sps, leathers, zoos, shrooms, clam, fish, shrimp, rbt, white sebae, fromia star