I agree with Mr Reef on everything. You don't really need that crazy of a filter on nanos, the reef will do that itself. On my 10 gallon I just used a backpack filter with sponge only to catch big peices of debris. You should definitely get a good protein skimmer though, they help nano tanks out a lot. Otherwise, you'd be doing daily water changes to keep the water column clean.
Follow my signature to a livejournal blog I made a while back while setting up my 29 gallon nano cube. (Scroll all the way to the bottom of the page and read going UPWARDS) I haven't updated it in over a year, but it's a good source to use to see what steps you could take, although you can change stuff around as you like. I don't have a protien skimmer listed on it, but I do use one.