Troy is right, after you see what a good quality skimmer can pull out of the water you will say "wholy crap!"... or something along those lines
It makes you wonder why you would never want to pull that stuff out of the water. Just my opinon.
If you decide to get a skimmer someday a sump gives you better choices for skimmers aswell (aposed to the meager hang on choices available)
Mag 7 will work ok. If you have all the pieces I say why not hook it up?