Pex
 

Has anybody used Pex to plumb their sump to display tank? Seems like it would be a quick, cheap and fool-proof procedure.

PVC is the way to go. JohnGuest or other quick connect fittings are big $$$. Other pex connection fittings use copper/brass/steel which isn't salt safe.

PVC would be much, much cheaper versus pex fittings (ie; 1/2" pvc 90 = $0.42, 1/2" pex 90 quickconnect = $4.59)

Never considered PEX.

When I think PEX, I think household plumbing to my tap-sets and toilet, not running 1" return line or 2" drain.

There is flexible PVC (one name/brand is Spaflex) and uses standard PVC fittings.

Spaflex looks like it might be a good idea too, and I think it is available in the local hardware store here.