The message
from "JohnB" contains these words:

I would like to attach a strip of rubber liner to the existing edge to
effectively raise the edge by an inch or so. I have initially tried using a
strip adhesive on a roll that is carried by a white backing paper - not sure
of the name but intended for sticking patches to the liner.


Anyone any other solutions? Any mastic like substances that will stick to
the butyl and give additional help? When completed it will be covered again
and not subject to significant movement.

It is not really practical to lower the waterfall to lower the water surface
below the edge.

There is special adhesive for sticking butyl to butyl supplied by butyl
stockists. When I had a leak, Midland Butyl or Pond Liners Direct (can't
remember which but can look it up if you're interested) posted me a tube
very quickly for just the cost of the postage. I seem to remember the
adhesive cost about £8.
Ignore this if I've misunderstood what you want!

Janet G