Ok, I spoke with little Giant on the phone (My last pump was from them) and I don't speak chineese. They said as long as the pump has water flowing into it by gravity, it can definitely be oriented vertically, as these kind of pumps are NOT self-priming. Thanks for the help. Bye the way, man were they ever a big help on the phone. They spent about 45 min with me question after question. I felt really bad about buying a chinese pump (or whatever). I didn't even think about it. I got the pan world because they are sealed (no oiling) and the little giant was not. Now I may go back to the L.G.