pm bullet 2 skimmer - questions before setup

[robzilla]

just picked up this skimmer to go into my 90g then into a 120g when i get a chance to set it up


what are some things i need to consider, should do.....
this type of a skimmer is new to me and any ideas would be great
going to be running it with a gen x pcx 40 pump.


looks like it will fit, just barely under my tank. the return line will go back into the sump with a straight piece of pipe and then an elbow down.
could the pump be plumbed in with an upside down "U" type of piping or semi rigid piping into the sump for the intake? the pump will below the level of the sump's water line. is this correct or does the pump need to be above the sump's water level?