"Phyllis and Jim Hurley" writes:

Something like TREX (artificial deck wood) might give you permanent
material. Haven't checked about leaching from it.

Can I use the pressure treated wood as sort of moulding on the edge of the
pond? Or will it poison fish if it comes in contact with water?

When I researched Trex for a cover for a large (12' x 6') filter I was
dismayed to find it not recommeded for continuous high humidity. I don't
recall if it said anything about ground contact, you might want to check.

HTH