Just a typical well, run through a pressure tank like would be used with any home.
From the hydrant you would run a 1 inch sprinkler hose with a brass sweeper nozzle on the end. The size of the nozzle dictates the flow rate, and the pressure in the tank dictates the speed with which the water exits.
This system is definitely NOT as efficient as a normal airlift type aeration system, but if you're delivering water from a pressure tank anyway, you might as well use the energy that's been stored and turn it into a water jet. In general, circulation systems aren't able to tap into the natural buoyance of bubbles to oxygenate, so you typically would spend more dollars per pound of oxygen created than you would with a regular pump/bottom diffuser setup.
The nozzle is placed parallel with the water's surface, about one inch below and sprayed in a manner that the pond circulates. The pressure from the nozzle creates tons of bubbles, but the real aeration comes from the fact that, like an airlift system, it increases the air/water interface by continually exposing new water to the atmosphere, and the oxygen contained therein.
