It does use gravity to do the major pull, but if you can dump using a stinky slinky, you can dump with the flojet.
I have the portable one. I really only use it at home. On the road at dump stations, a stinky slinky is just too easy not to use.
At home, I simply attach it to the dump point (it connects like a stnky slinky) and then use long jumper cables to connect it to the house battery on the other side of the RV. It does a great job of moving everything through the attached garden hose and down the clean out pipe.
I have found that the power is a bit reduced if I'm not connected to shore power. It still works, but it is more powerful when I hook up.
I did have the fuse blow once, easy to switch out. And I had the blades lock up - just a quarter turn on the screw and they were fine.
Otherwise no problems at all. And so much nicer than connecting multiple stinky slinkies and having to manually "lift" the contents down the slinky hose line.
1975 American Clipper RV with Dodge 360 (photo in profile)
1998 American Clipper Fold n Roll Folding Trailer
Both born in Morgan Hill, CA to Irv Perch (Daddy of the Aristocrat trailers)