Quote:
Originally Posted by
bekko 
Maurice has nice "gutter connect" greenhouses. His ponds are not lined although I believe he uses some plastic to help control erosion around the edges.
The "hoop" or "tunnel" style greenhouses are much less expensive but there are limits to how wide they can be and you do not get expansive open spaces. In either case, you probably want long narrow ponds so that there are no columns in the water.
There are advantages to lining the whole pond and putting a soil overlay back on top of the liner. There is no seepage for water conservation, there is no erosion of the sides at the water line, the koi cannot root out holes in the sides of the ponds, you have control over the soil characteristics and soil quality, the pond can be completely dried or sterilized for pathogen control and to oxidize organic matter. It is just a much more manageable situation that way.
-steve hop