Topic: auto bilge pump installation
I have my manual one with a string tied to a corner of it and then tied to an engine mount. That way, I can raise and lower it easily.
When I installed it, I attached it to too long length of new, high end hose, then wound it through to where it was attaching to the diaphram, then cut the hose. That way, I wouldn't err and make it too short! I made sure the pump was flat down into the bilge. The old one had been sideways! as the hose was a little too short! Our bilges are deeper than we think...I think I used 6' of hose.
I don't have an automatic one, as I don't trust it with the batteries, or the batteries with it! ;-)
Good luck!