do not i repeat do not go into salt water with a nano! go with the 55, trust me,
1. youll be able to have more than just 1 or 2 fish
2. lots of space for coral
3. it may be expensive, but the cost is only heavy in the beggining with the live rock and the sand and other equip ment
4. when the tank gets cycled add half of the cuc (which is hermit crabs and snails) then wait a week and add rest, then wait another week and then get 1-2 fish only. then wait 1-2 weeks and if things are fine get 1-2 more, eventually youll be stocking by for every 2 similar sized fish divide by 2 and thats what you can get, for a 55 that wouldbe around 10-17 small fish or 2-5 large ones
5. coral is 2 week wait times and you need to do research for them.
trust me i have a 20 gal. have followed these rules, and nothing has gone wrong (knock). the tank IMO looks real empty with only 2 clowns, but it's nice.