My setup is similar ~1700gph
 

I just pulled my dart and replaced it with a snapper. But my setup is close to what you are planning, but without the sea swirls. I would recommend going with 1.5" spaflex (what I have) as it will give you a bit better flow. I get about 1500-1700 gph out of the dart going up 6ft to the tank with 2- 45's,3 90's and gate value and a swing check in there.



Oversize pipe also makes it a whole lot easier if you want to ever upgrade pump. Just swap out the pump and go. Even better with the dart and snapper becuase the arfe the same wet end. Just undo one, and put the other in place. :)

Anyway, you'll get pretty good flow out of the dart. and a BIG +1 on the gatge valves -- I put one before and after the pump with a union to be able to remove the pump for service without draining the sump.

Christy your Dart can handle it. I always prefer, if space permits, a valve and then a union between the sump and return pump and then a union and then a valve coming out. This makes pump replacement a snap and allows you to control flow on the return. I don't feel it's necessary to drain the sump to change a pump.:wink: