Thanks, Kevin. You can't see it in the pix but the stems on this plant are
thicker than
parrotfeather and the little flat/wide/short dogeared leaves are arranged in
helix-like whorls
along the stems which branch at long intervals. It builds up quite an
impenetrable mat that frogs
and fish have a hard time getting through to get to the surface. I got it
from an aquarium store
and they gave it a name ending, I think, with ...ix. I would like to get it
started in my 3 ponds
to use up nutrients so I can harvest it for fertilizer and mulch.