External Backup Pump?

[KenRexford]

The idea of a backup return pump in case the existing pump fails seems like a good redundancy. However, fitting two pumps into the last chamber is often not possible. Replacing the sump with one that has a bigger last chamber would be a pain and expensive, and I am really maxed out anyway on what fits. Putting a bulkhead into that last chamber is essentially the same thing.

Two thoughts occurred to me. One is an external pump that is self-priming, where just an intake pipe is dropped into the last chamber.

A second is a sort of priming function. Think CPR hand-on overflows, with a Tom Aqualifter to pull out air and prime the overflow siphon. Maybe something sort of in reverse might work with water pumped into the intake pipe so as to enable the flow to start?

Has anyone thought of any approach to an external pump used solely as a backup and add after-the-fact?

 

[Lbrdsoxfan]

I considered it once upon a time when I had a old reeflo pump lying around. Ended up with too much complexity and fear of leakage from running a external pump (it isn't if but when a seal blows).

I have ran dual smaller AC pumps in a return chamber, in parallel, with check valves on the output side for the same effect (redundancy).

In the end I now just run DC pumps & DC power heads with battery backups.