Engineer48 says Rossi told him that most of the water flow through the Big Frankies was due to a single master pump and that the Prominent pumps were used as topping up pumps. I don't see any independent route for entry of this water into the Big Frankies so the water flow due to the master pump must be straight through the Prominent pumps and superimposed on the due to the pumps themselves.
I think the relationship between water flow established by pressure on the inlet and flow due to the action of the Prominent pump itself is something we could determine empirically with Alan Fletcher's cooperation. It could very well be that the 83 L/hr required of each pump is not possible even with external pressure but then maybe it is possible. And even if 83 L/hr is possible I really do wonder about the 125 L/hr that seems to be needed from each pump when the plant is in the configuration it seems to be in on the last day of its operation (only 2 Big Frankies operating).