How much would it cost to have a 5.5 gallon nano with I guess just one little fish. How hard exactly is it? Probably just gonna do freshwater, but was just wondering. Do you have to have a protein skimmer or will the live rock do it? How do you make sure there's the proper amount of salt other than with that floating gauge thing. Do you just do little water changes? Or none? Just get the amount of salt right and it'll stay in there? Or do you fill it back up with fresh or salt water? Probably going to not do coral or anything because of money and skill level with saltwater. Maybe just some sand, live rock, and a clown fish. just found this: http://www.tfhmagazine.com/details/articles/how-to-start-and-maintain-a-nano-reef.htm