In article m
writes:
our sides were up and down and concrete block, but we used rug underlayment tucked
behind the top block and hanging down into the pond. no "staples" and the pressure
of the liner and water keeps it in place.

Is this the pond on your web site, or a previous one? I've been
looking at
http://weloveteaching.com/mypond/2000/p2000.htm
as I'm thinking of a similar style pond.

I thought that pond was framing lumber and plywood. Did that hold up okay?