Thanks for the explanation and confirming my suspicion.  Do you know if there is a control valve out there that would shut off the flow completely?  I like the way I have it setup currently so will probably just leave it but curious if there is another option.

Not trying to hijack the op's thread here but this question seems relevant to the question at hand, but I had the thought of adding a second pump to the setup to increase the flow, I ran 4 gauge wire back to a distribution block at the planter so should have the current capacity.  I have two tanks on the planter the feed the single pump, my bypass only goes back to one (Well it goes back to both tanks but I leave the return valve shut off on one).  Can two pumps feed the same manifold and bypass or would that cause problems with one pump or the other?