Most people drain to the skimmer compartment first either through a filter sock or not, it's your preference, then they tee into the return line so they can adjust the amount of flow to the fuge by means of a ball valve. You don't want the full flow of your sump going through the fuge, the idea is to have slower water movement in there so the macro algea and organisms have time to absorb nutrients and not get disturbed by turbulent water. As for the skimmer check out these links for setup and tuning the SWC 160
http://www.youtube.com/user/mrsaltwa.../2/MLAgZopwyDM ,
http://www.youtube.com/user/mrsaltwa.../1/p6_t5ziZ3vU