Since I received no responses so far, I hooked up the pump and primed it. I put it below the tank water line to start, and water came out the discharge end without
running the pump.
I must not understand Grundfos model markings, because an explanation I saw on one of the web pages says the first number is the inlet size (15mm) and the second
number is the amount of decimeters of head. Well, 145 decimeters is 14.5 meters. That is a lot of pressure. However, the pump could not even do 6 feet of head.
A total waste of time! I saw the water make it out of the first collector, but did not make it to the second collector.