Regarding fish, I must admit that I don' t really want to have to
replace a lot of water every week. As I said, we had a few goldfish to
make the pond more exciting, and they seemed happy enough with the
naturally fluctuating water levels. It never got dangerously low, and
if it did, of course I would take steps.

I respect both Joe and Jan's dedication, though at the same time I do
tend to believe that nature will usually look after its creatures.
Despite no filtration, we have a lot of oxygenating plants in the pond
which seem to do a pretty good job of keeping the water clear. If I
don't replace the fish it would be because I don't want the heron to
come and get them again. I'm reluctant to have netting over the pond,
which seems to detract from the pleasure. I'll see.

Another thing against the fish is that they tend to eat our frog spawn
and tadpoles -- and a big part of the reason for creating a pond in
the first place was to encourage frogs in the garden. (We have a big
vegetable patch, and want the frogs to eat the slugs!)

Hmm -- I seem to have got off the subject of my pond liner, but no
worries. These are all interesting points that are teaching me things.

Thanks -- Will