HI & Welcome, First thing I suggest is read seffieuk/ trod journal on there experiences. Its a couple of hours of good fun but also good information. The two books I got to start with was "saltwater for dummies" & "The new Marine aquarium" (very good). The main thing is to ask questions on here. I have been running my tank for just over a month now & ths forum has helpalot. No questions is too silly/ daft.
Note that below they say bigger is better, that is correct, however they should say once you start a nano, yo will want to upgrade asap, which I want to now
All the best.
I just bought The new Marine Aquarium book the other day.