I was told that a bilge pump should be piped straight up as far as it will go, usually just below the cabin sole, then an easy bend and downhill to the fitting. That way, the minimum amount of water stays in the hose when the pump shuts off, and water that gets into the thruhull from outside drains back out.
1975 32' Flybridge Sedan, twin Perkins 6-354 diesels, 1:1.53 velvetdrives, 16 X 19 props. Merritt Island, Florida