(I can't find any English lit on it, but my Grundfos Ejektorpump (had to go out and look at it to see what it's called; perhaps the correct translation is ejector pump rather than injector pump?) is in a 85m deep borehole and works great. It's 40 years old, heavily used and never serviced and quite a puzzle how it's still going. I have no idea if they can pump from deeper than that)