Twychopen is right, that's a 125. Make sure to clean up those bio balls before you use them, the same way you're cleaning up the rock. A lot of people don't clean them like they should, and now sitting dry in your garage they're gonna get funky.

A lot of people put the skimmer in the sump because there isn't much room under their stand. But your tank is long enough, you could probably have the skimmer outside of the sump with just the skimmer pump inside it. Leave some valuable space open in there. There's that marineland brand skimmer that has the pump built into the footprint, aggiereefer had one. Don't know how it would perform on such a large tank though.

Oh, and welcome to MAAST!