And Mike is right. The aqualifter can be weak depending on the application. For me, it works because the pump sits low on my stand. I have an ATO reservoir that's about 36" tall, so it sucks the water up 36" and then drops down another 36" to the floor and passes about three feet of airline on the floor, gets to the pump, and I have the hose hanging from the top of my plumbing (drains) due to the syphon effect (any lower and the pump wouldn't stop pouring water). So it goes up another two feet and then empties into the sump.
If you're gonna have your pump above the ATO, then go with something stronger. I had problems with my aqualifter in my QT where the pump was on top of my ATO and the tank was another 20" above the ATO.
It just depends on your setup....It's the head height that gets you with the aqualifter pump. You can have airline stretched across the room as long as it sits low with no problem, but once you raise the airline, the pump will struggle to push water.