I guess I should have been more clear about the horizontal pipe.

Since we were talking about feet of head, what is the conversion of horizontal pipe to feet of head? I think I am probably about +1 foot of vertical head from the level of water in the pool, to the placement of the pump, but its the horizontal run which seems to be dictating pipe size and pump.

I think the chart you posted shows a different "quality" of pump based on which efficiency curve you need to be on, which in turn is based on flow rate (based on pool size), and dynamic feet of head (based on pump placement). Is this interpretation not correct?