Richey this might give you a start on your ram pump.
http://www.clemson.edu/irrig/equip/ram.htmI also got to thinking, depending on how much drop you had from the high water source and how much volume, then piping to the lowest pond, maybe you could do something like St. Petersburg, Russia and Rome, Italy did for water fountains. Collect water at the high level for pressure at a lower lever. In the 1800's Alaska water hydraulic gold mining was done by taking a water stream up high and piping it through large pipes and chocking it off at the bottom in smaller diameter pipes which created very high pressures that they could wash away the sides of mountains looking for gold. I could see at your lower level pond having a high spraying fountain for aeration for free after the piping expense.
