I have this new to me system that uses 2 pumps and draws from a pond somewhat below the elevation of the watering area. One pump is at the pond and pushes the water up the hill to the 2nd pump and then out to the zones from there. The 2nd pump is probably 15-20 ft. higher in elevation. My question is should both pumps be the same HP or not? My guess would be the one at the pond, lowest elevation should be higher capacity since it has to push it up the hill.