3 ton system for 2000 sf in the Memphis area. Planning on putting (3) 800' loops, with 350' per loop near the edge of the pond at 5' down which is pretty darn wet (standing water in the 30" hole I dug). Concerned about whether there will be adequate heat displacement through the water and black clay, or whether the heat will stay in the same location since there is no water circulation to speak of. Also, the contractor is planning on running the raceways in a big loop, with an outer loop, an inside loop, and a loop in the middle of the two. The three sections carrying heat away from the house will be 24" apart, as will the three sections going back to the house. The outlet and inlet sections will be about 24" from each other at the closest point (for about 30') but will mainly be at least 4' apart. I mention this as it seems that the outlet side will have the harder job, so to speak. From what I've read, the 24" spacing is not an issue if the loops are long enough.