Look for some Sani-tred....its great for coating masonary for use
with koi. As long as the paint does not have any algae cide or copper
in it, or other heavy metals as a filler it shuld be pretty wel fine
to use. Sani tred I know is used quite extensively by a lot of
commercial ponds. Rustoleum makes a 2 part epoxy paint that is good
for constant submergence in water and is harmless to fish once cured.

Back to Sani-Tred. It has other products that go along with it. One is
a thick base like putty used to fill in gouges or large cracks or even
make a fillet inth corners to reduce chances of koi from bumping and
bruising themslelves or filling in corners to prevent detrius and mulm
buildup. It also serves as a filler aorund any pipes etc that may
enter the mas0nary. Then the finish coat is applied just lke any
typcial coating. I have the insides of 4 burial vaults and one 1000
gal septic tank coated with sani tred and have never had a problem nor
a seep with the stuff. I use the burial vaults and septic tanks as
holding tanks for fish or QT tanks...

Check it out at:

http://www.sanitred.com/WaterFountain.htm


I know of a ton of ponds that were made of masonary / block
construction and even some of plywood, thast was coated with sani
tred, and they worked just fine.......
On 12 May 2007 16:40:05 -0700, Delbert wrote:

For several months now I've been working on a small koi pond for the
back yard. The shell is formed out of concrete block sitting on a 6"
thick concrete slab. Total capacity of the pond will be about 1300
gallons with a small waterfall at one end and a skimmer at the other.

The concrete block work is now done and I'm turning my attention to
painting. Knowing that concrete block is porous, and will raise the
alkalinity of the water, I need to find a good paint to cover
everything with. My first thought is to use swimming pool paint as it
is designed for constant water exposure.

Has anyone had any experience with the "Smart Seal" line of paints
(http://www.smartsealco.com/pool/)? They have epoxy, acrylic enamel,
and synthetic rubber products. This brand caught my attention because
it is carried by a local vendor.

I contacted the company via e-mail to ask if their paint is approved
for fish pond use. Their reply was that it is not approved for fish,
but that they have heard of people using it. My guess is that they
have just never gone through any type of formal testing for that sort
of application. Still, considering that a swimming pool has people in
it, you wouldn't think the paint would be allowed to leech toxic
chemicals.

Has anyone used this or another brand of pool paint in a koi pond? If
this is not a good idea, I'd really like to hear of some alternative
coatings which I can get in the Eastern US.

Thanks!



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I forgot more about ponds and koi than I'll ever know!