Advice? External Pump

Put in true union fitting so pump can easily be removed.
Sounds like it is suckling air.

 

http://www.bulkreefsupply.com/schedule-80-union-slip-x-thread.html
Something like this. You should be able to get at any store with plumbing supplies

 

That pump is not designed to suck up, it is designed to push up.

It needs to have the inlet below water level. You will need to drill a hole in the bottom of the sump and install a bulk head.

A 90 degree turn on the inlet is also a no no. The pump really needs to have a straight shot into the water supply

 

That pump needs to be mounted like this. I wasn't able to have a straight shot like I wanted because of stand limitations but I tried to keep the flow out of sump greater by using as big a pipe I could to keep pump fully fed with little restrictions.

 

Roman brings up a good point about how space restrictions can mandate a pump to be mounted in a unique manner. Sometimes you have to get creative with external pumps. Is there a reason why an internal pump is not suitable for your setup?

 

You may be able to get it to work in that postion if you add a check valve near the sump. Not sure how much suction that pump has but if you prime the line with water it may work, and the check would keep the line primed when the pump shuts off.

 

acrylic sumps are easy to drill to put a bulkhead on.

 

Iam with bxr. External pumps. And especially the pan world ones are meant to run below water level. They are not a sealed internal wheel meaning that the spinning wheel does not have a separate chamber for nin let and outlet devided. It can't draw pressure. They are meant to push, not pull. Specifically even the ps series that has some 40 foot of head pressure doesn't pull water, and trying to take water from above the waterline voids the pan world warranty as am fyi.long and short. Those pumps won't draw water like that.