The answer to your question is how much water do you want to put through the line. The volume of water that can be put through a pipe depends on the head. This head is both static and dynamic head. With a large enough pump, you can probably multiply the standard flows that we are use to seeing by several times. The amount of water being drawn through the pipes in your case would have to be calculated by looking at head losses and pump charts and working backwards. With some head loss, the pumps will not pump the rated flows, and you will find the balance between flow and head loss. This link shows head losses for pvc pipe up to 5" http://www.plumbingsupply.com/flowchart.html
Zone 7 A/B
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