what type of cement to use for pond?

I agree with Rich.. concrete is best left with those that work with it
daily.
For mine, I had a gunnited pond. has bottom drain, marginal shelves, and
skimmer, as well as extra (currently not used) side pipes, for future
additions.
Had it sealed with standard sealer used to finish pools. Color I picked is a
natural brown.
Believe it or not, it was only $1500 more than similar sized liner pond if
done by nursery!
Nothing leaches significant out into the water when properly sealed.
Additionally the pond is guaranteed for my lifetime, against leaks, etc.
I have added EPDM lined falls, stream, and bog garden, so you CAN change
your configuration once its "poured in
place"
Happy ponding,
Greg


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"RichToyBox" wrote in message
news:le2Ra.73265$N7.8563@sccrnsc03...
Concrete for a pond is a job for a professional. Whether it is gunnite,
which is a very dry spray on concrete, or whether it is ready-mix that
must
be placed in formwork, neither is a job for the untrained. The EPDM or
similar liners are much more forgiving.

If you use concrete, as soon as the concrete has been placed and finished,
and the workers are out of the pond, cover the surface with polyethylene
sheeting to keep the moisture in for the first week. Add water and leave
the water for a month. At the end of the month of curing, the concrete
will
have most of its strength and watertightness. Because the hydration of
cement yields a lot of calcium hydroxide, it will cause the water to have
a
very high pH( potentially 13). Drain the water and allow to air dry for a
couple of weeks to allow carbon dioxide in the atmosphere to react with
the
calcium hydroxide to form a calcium carbonate (limestone) surface
hardening.
This will make the concrete more watertight and reduce the ability of the
calcium hydroxide to migrate to the pond water. Also drying allows the
pores to dry of liquids filling with air which acts as a dam to water
flow.
Fill with water and monitor pH. If it is climbing, above about 9, remove
the water allow to air dry for another two weeks and try again. If it has
not stabilized, then you should coat the surface with a surface coating
like
Thoroseal, or pool paint.

Some of the skimmers on the market have concrete collars that can be
bought
to fit them, and some of the bottom drains have a concrete extension for
going through the concrete, rather than the bulkhead fitting for rubber
liner.
--
RichToyBox
http://www.geocities.com/richtoybox/pondintro.html


"matt clark" wrote in message
om...
I am putting a new pond in my back yard. It is my first time doing a
project like this. I have pretty much got the hole dug at about 3'5"
and i have already purchased the rebar. My problem is that i cant seem
to figure out the best type of concrete to create a liner. I was told
gunite and portland. but im not sure. Also will I have to seal it
regardless of what type of cement i use? Soo many questions. Also if
anyone has any tips i would appreciate any help on sealing the drain
or plumbing tips.

Thanks in advance.