I am also planning on installing a geothermal unit but it will be a closed system with a slim jim which does not take up much area. If I do not use the slim Jim it will be a coiled loop which still does not take up much area about 10 foot by 12 foot as I remember. I have narrowed it down to about two manufactures because of problems some have had with the other manufactures. On the closed system I have talked with others that have it and the water temperature increase is very slight near the coils in the pond.
