Yes, the safety connectors can share the same battery and charger and keep in mind that we are just trying to sustain life and conditions will not be normal, even with flow you won't have heat/cooling or light. I generally advise just backing up one or two pumps to get oxygen exchange and not trying to keep normal reef flow going. We also have to be concerned with battery life and realistically this is not going to be a solution past about 24 hours unless we have perfect weather, after that temperature becomes a real issue.