I am setting up a 55g tank with fish and live rock once I gain more experince I want to turn into a reef system and I want everything I purchase to be ideal for a reef tank. I was looking at various skimmers and it appears that some skimmers are designer specific to reef and others not, (biological factor)? Can someone please recommend a good skimmer that is compatible in both systems. Although, I do not know much about skimmers from what I have read I think I would prefer a hang on design, I want something that is easy to use but that is also effective and dependable. Also, I currently have a 125g cichlid tank I may on day turn this into a saltwater tank is there a skimmer that would not be to powerful for a 55g but effective enough in the 125g. Thanks