I would have never used pvc either, but that's how it was set up when I bought it with an iwaki water pump. I was thinking of flexible tubing myself. It looks like a standard garden hose would screw right on my pump, is that not possible.
The pump is set up on the opposite side of the bulkheads so it the pvc goes up 1 foot, parallel to the ground for 3 feet, then up through the bulkhead 3 feet, then back down 3 feet, that's not counting the foot that is attached to the intake side coming out of the wet dry sump