It may be worthwhile to push for a lightweight flex liner dropped inside the
stock tank. That wouldn't be the same as having one in the ground, as far
as the likelihood of a puncture is concerned. If it did puncture, we
wouldn't lose any water from it. Also, I think a pinhole big enough to
really drain a pond wouldn't be big enough to allow any nasty compounds to
mix with the pond water. I will do a search on polyurea. Thanks for the
heads up.
"Janet" wrote in message
news


--

"Derek Broughton" wrote in message
...
Janet wrote:

Ann there has been alot of talk about spray in bed liners on most of
the
major koi forums. The spec sheets have been posted and the
manufacturers
don't recommend it and explicitly say it's not fish safe. On the other
hand there is now a spray in pond liner that is fish safe. Do a google
for
GatorGuard and DragonKote. All the info is there.. )

Note, there is an important difference between "not fish safe" and
"unsafe
for fish". The former merely means that the manufacturer has no
interest
in testing and certifying that the product is fish safe. Especially
since
they can create a "certified" product that they can sell at a premium.

The old-timers here will remember that, at the time I started into
ponding,
sometime in the mid-90s, one of the hottest debates was over the use of
pond-safe EPDM and EPDM roofing liner. Firestone, the major
manufacturer
of both, insisted that the roofing liner was not fish-safe, but many
people
used it without trouble. I know of one DIY study that claimed it killed
test fish, but I also know of dozens of respected ponders who never had
a
problem.

What it really comes down to, is if you are starting off with a water
garden
with a few cheap fish, don't waste your money. If you're starting a koi
pond, and planning to spend hundreds or even thousands of dollars on
fish,
don't _risk_ your money.

otoh, either kind of spray-in bed liner seems like a ridiculously
expensive
way to build a pond.
--
derek

Derek that is very true to a certain extent but not the case with the
spray
products, aka polyurea. The original chemists who worked on polyurea
applications are dead set against using it near fish. They were approached
to develop a product that can be used in ponds safely. It's chemically
very
different from the bed liner products. You're right Derek, the spray in
products are not for everyone, but for those with poor soil conditions,
ground water issues, etc it's one of the most economical ways to go.
Especially when one takes into consideration the cost of building a pond
in
those types of conditions. The other major plus is the warranty, 20 or 25
years even with exposure to UV. Now add in that expansion is not a
problem,
it can be sprayed onto itself, and there are definite advantages. The
only
possible drawback at this point is that it's not been put to the test in a
cold climate. We keep trying to talk a certified installer into coming
north
and doing a test pond. The product has been tested under labratory
settings
for cold, but no real life stuff..
Janet in cloudy Niagara Falls