Need ADVICE: 3700gph pump - what size plumbing

[CrAzYNeSs]

Keep in mind that a 1" pipe using gravity feeds maximum flow rate is 600 GPH in OPTIMUM conditions. I'm "guesstimating" that a 1.5" pipe can do ~900 GPH.

 

[BigLinc]

should i put a ball valve on the pump site to throttle it back and run two 3in returns, i mean am i going the wrong direction with this pond? i was trying to get close to 3 times turn over a hour

give me advice, i hate doing things twice

 

[BigLinc]

anyone?

would it help to have another pump at the filter?

 

[BigLinc]

well ive done some thinking and i may just go get a stock tank and use that for a sump with a pump in the pond and a pump in the sump