| This may not be completely true, but based upon my recent shopping for my set up, it is a good thing that you are looking at a skimmer that can 'skim' more water than your tank holds. This coupled with the fact that a 55 gallon tank, after adding rock and sand, will hold less than 55 gallons, you should be good.
However, I do not know anything about brands and cant really help you decide which is best for your situation.
Good luck though! It is an exciting time, isnt it? I felt like a kid trying to sleep on christmas eve when I was buying my set up and getting closer to having my tank! | 
