My 2 acre pond averages 18' deep when full. I aerate with a surplus Gast rotary-vane pump, back-fed into a 75' soaker hose wrapped around a 5 gallon bucket (duct taped in place) with a rock to weight it all down. Very basic, but very efficient, and about $150 to build. After 30 days of 24/7 aeration, the entire pond is wihin 1* degree temp, top water to bottom, and stays that way Spring through Fall. Hope that helps.
