Love the design.... too bad i already built my sump. Anyways, I'm having issue with the return pump empting my sump. My tank is a 250 gallon and has two drilled hole 1.75" with 1" bulkhead. I have 2 90 degree elbow, one on each bulkhead. My return pump is a 1000 GPH. Was curious if anyone had suggestions on how I could increase flow to my sump. I noticed you using a Mag18... what size pipe are you using? Thanks for any response.