it's a mixed reef tank including, lps, sps, softies, rics, muchrooms, sponges, gargonians, etc. also have tangs, reef safe angels, anthias, gobies, jawfish, chromis, maroons, cardinals, wrasses, shrimp, etc. i have like 15 fish now and would like to get a few more species. i have a coralife 220 skimmer on there and i think it works fine, i haven't had any other kind so not sure if i could do better, but i think the corallife is causing all the microbubbles in my tank. i don't want to spend a lot of money on it but i thing everyone say that but i also know that is skimmer is very important, so i would like to get something that is energy efficent and very productive.