The first pond I had was a garden pond, about 12'x6' made of brick and lined
with concrete. It came with the house. It worked well for so small a pond,
and the fishes and frogs and plants liked it.

I wonder if any of you have suggestions for concrete. There are a multitude
of types and additives. However, I would like to know exactly what type is
recommended for lining a pond. And what additives to avoid.


Michael
New Orleans, Louisiana USA
================================================== ==============

Our pond is concrete. 12 x 22 ft. contoured. We have clay soil, so
we wanted it strong. It has a 12" grid of 3/8" rebar. The floor and
sides are 4" thick of dense concrete. In theory, it is driveway
thickness. We installed it in 2 pours: floor and walls. The joint
(between floor and walls) has a comercial tarlike strip about 1 x 1"
runs along the base of the wall, just in front of the rebar. It
swells if it gets wet and seals the joint. It is what they use in
skyscrapers. We have a 'deep well' (=old septic tank) in the pond.
It has special reinforcement around it and the tar strip at the
joint. We are now at 10 years. When I cut the circulation, we ave no
discernable leakage (as teasted by comparing a milk bottle and the
pond for evaporation rates). The density of the concrete is enough to
prevent leakage through it. Water can osmote through concrete if it
is thin enough.

If you are thinking of lining the pond (as we had to do with the
porous septic tank, there are nice cements to coat and waterseal.
Those with fiber glass and designed for such applications are a bit
less likely to crack. Ours has held well.

If you re covering brick, etc, I would be most concerned about
settlement cracks. I don't have any data on how much strength might
be needed.

If you have total freedom as to the new pond, you might consider an
EDPM liner. No settlement problems.

We kind of like our cemet as it allows us to walk in it without
concern about making holes. Loads of ponders here have EDPM or
Permalon liners. They will offer their views, I hope.

We have a son in NO and get there from time to time. Where are you
located. I am thinking of the wetness of the ground inthe city
itself. Our son's home was in Lakeview and took 11' of water in
Katrina. Still not rebuilt. He lives in a FEMA trailer!

Jim

Keep us posted.

Gunite or shotcrete.

"MLF" wrote in message
...

The first pond I had was a garden pond, about 12'x6' made of brick and
lined with concrete. It came with the house. It worked well for so small a
pond, and the fishes and frogs and plants liked it.

I wonder if any of you have suggestions for concrete. There are a
multitude of types and additives. However, I would like to know exactly
what type is recommended for lining a pond. And what additives to avoid.


Michael
New Orleans, Louisiana USA
================================================== ==============

"MLF" wrote in message
I wonder if any of you have suggestions for concrete. There are a
multitude of types and additives. However, I would like to know exactly
what type is recommended for lining a pond. And what additives to avoid.

"Pat" wrote
Gunite or shotcrete.


I thought of that. However, the soil here New Orleans is entirely silt - no
rocks, pebbles, or subsoil of any sort. Silt down to about 500 feet.
Building on it is a challenge. The city sewerage workers refer to the ground
conditions more than a meter down as "puddin".

Swimming pools are rare, a surprising situation in a warm climate like this,
probably because of the poor soil conditions. Most pools are
gunite/shotcrete with a plastic liner and most all have settling problems
(no surprise). Any of any size are built on dozens of pilings driven into
the ground - a very expensive proposition.

I'm beginning to think that only relatively shallow ponds are practical
here. I had one that was 2.5 feet and it had settled (over 50 years) about 2
inches. I'm guessing that anything will sink unless some really large
oversized concrete pad is used at the bottom.

My particular question was concerning the type of concrete. I don't want to
poison the fishes, and I don't want to use a liner, so the components of the
concrete are very important. Gunite and/or shotcrete may be suitable, but
I'd like to hear that from someone who actually has a concrete pond like
that with fishies.


Michael
New Orleans, Louisiana USA
================================================== ==============

My particular question was concerning the type of concrete. I don't want
to poison the fishes, and I don't want to use a liner, so the components
of the concrete are very important. Gunite and/or shotcrete may be
suitable, but I'd like to hear that from someone who actually has a
concrete pond like that with fishies.



New concrete turns the water alkaline. Let it age before use. Or roll on a
coat of asphalt emulsion.

In article ,
"Pat" wrote:

New concrete turns the water alkaline. Let it age before use. Or roll on a
coat of asphalt emulsion.

Asphalt emulsion is can suffocate fish until it completely cures.

The MSDS for asphalt emulsion is at:
http://www.neyra.com/MSDSjena.htm

It says:
When spilled in waters containing fish, material will suffocate
fish until it settles on bottom.

Most fish hatchery ponds are lined with hot-mix asphalt. Then this is
sealed with asphalt emulsion because a bacteria detrimental to fish life
can find a habitat in the surface voids of the hot-mix asphalt. The
Asphalt Institutes specifies using a CSS-1 or a CS-1h asphalt emulsion.

http://www.asphaltinstitute.org/Uplo...s_Lined_With_A
sphalt.pdf
--
Pardon my spam deterrent; send email to
18,000 gallon (17'x 47'x 2-4') lily pond garden in Zone 6
Cheers, Steve Henning in Reading, PA USA

Local ponder here did his pond in concrete, similar to Jim, I think it was
4" thick. I remember them using muratic acid soaks, 1 gallon/1000 gallon
water. Seems you want to keep it acidic for at least a week, by adding more
acid as needed, drain, rinse, fill, wait, and test pH. If 7.5 or less after
a week or so, I'd think you'd be good to go. ~ jan
------------
Zone 7a, SE Washington State
Ponds: www.jjspond.us

Stephen Henning wrote:


New concrete turns the water alkaline. Let it age before use. Or roll on a
coat of asphalt emulsion.

Asphalt emulsion is can suffocate fish until it completely cures.

Same question, but slightly different angle. I am converting a pool
(shotcreted and plastered in 1987) into a pond. The plaster is now
off-white with years of dirt, scrubbing, and algae and slightly
pockmarked. I was thinking of coating this with epoxy paint (black or
dark blue). Any fish problems with that?

Chip

On Mon, 15 Oct 2007 15:01:44 CST, Chip wrote:

Same question, but slightly different angle. I am converting a pool
(shotcreted and plastered in 1987) into a pond. The plaster is now
off-white with years of dirt, scrubbing, and algae and slightly
pockmarked. I was thinking of coating this with epoxy paint (black or
dark blue). Any fish problems with that?

Chip

I believe epoxy is one of the materials of choice for such a
situation. ~ jan
------------
Zone 7a, SE Washington State
Ponds: www.jjspond.us

Jan:

That sounds like good advice. Certainly the alkaline in the concrete would
be neutralized by the acid if used repeatedly and is allowed to sink into
the concrete.

Michael
New Orleans, Louisiana USA
================================================== ==============




"~ jan" wrote in message
...
Local ponder here did his pond in concrete, similar to Jim, I think it was
4" thick. I remember them using muratic acid soaks, 1 gallon/1000 gallon
water. Seems you want to keep it acidic for at least a week, by adding
more
acid as needed, drain, rinse, fill, wait, and test pH. If 7.5 or less
after
a week or so, I'd think you'd be good to go. ~ jan
------------
Zone 7a, SE Washington State
Ponds: www.jjspond.us

The walls will become dark with algae fairly quickly. Would that
provide you with enough darkness? Woud there be anything gained from
the epoxy? Jim

On Fri, 19 Oct 2007 20:53:25 CST, Phyllis and Jim
wrote:

The walls will become dark with algae fairly quickly. Would that
provide you with enough darkness? Woud there be anything gained from
the epoxy? Jim

Epoxy seals and keeps the pH down. Not really a color/darkness thing. ~ jan
------------
Zone 7a, SE Washington State
Ponds: www.jjspond.us

Concrete, whether truck mixed or gunnite/shotcrete is made of Portland
Cement, sand, water, coarse aggregate (gravel or crushed stone) and
admixtures. The sand, water and coarse aggregates should not pose any
problems. Most of the admixtures are used in such small quantities and are
bound in the concrete, so I don't see a problem with them, either. I will
cover some admixes that you might want to use later.

When Portland Cement hydrates (reacts with water) it produces the calcium
silicate hydrate gel which is the stuff that makes the concrete stong and
water tight. It also produces as by-products heat which can lead to
expansion and then on cooling contraction that will cause cracking, and it
produces calcium hydroxide. The calcium hydroxide is in the form of pore
water, which comes to the surface, the pH of which is about 13. In air, the
calcium hydroxide solution reacts with carbon dioxide to form calcium
carbonate which is essentially just limestone, neutral pH. The calcium
carbonate blocks the pores making the concrete both stronger at the surface
and more watertight. It takes time exposed to air to get the carbonation
layer formed. With the high water table in NO, I don,t think it would be
possible to keep an empty concrete pond to allow the drying, since they make
ships of concrete. The longer concrete cures the strionger and more
watertight the concrete becomes. Curing requires a reasonable temperature,
which you have, and a constant supply of moisture. So as soon as the pond
has been poured, keep the concrete moist for a few days and then fill it
with water.

Water is the best and worst thing for concrete. During mixing and placement
the less water the concrete has, the stronger and more water tight the
concrete. Some of the mix water will leave the concrete through what is
referred to as bleeding, where the solids settle and the water flows to the
surface, leaving pores that are an avenue for water and chemicals to get
back into the concrete and cause problems. The concrete will set up before
all this mix water can leave, so some of it is just spreading the solid
ingredients out and not providing any strength in the end. After placement,
the concrete should not be allowed to dry, since the hydration reaction
requires water and this reaction, suipposedly goes on forever. So the
longer the concrete can be protected from drying the better.
The concrete ponds that I have seen that do not have some form of
waterproofing membrane painted on are usually allowed to sit for a year
before any fish can go in, doing acid additions, water changes, and pH
monitoring to see when the pH stabilizes at a safe level. The leaching of
the calcium hydroxide will continue for a long time, but will decrease in
rate, so the pond water will finally stabilize.

As far as admixtures, there are 3 or 4 that you might want or need. Air
entraining admixture is a must in northern climates to provide freeze thaw
protection to concrete, but it also provides some improvement in the
watertightness of concrete. Set retarder slows the initial harding of the
concrete to provide a little extra time place and finish the concrete, and
the warmer the concrete the faster it sets, so this one I think would be a
must. Set retarders will usually allow for less water in the mixture.
Water reducers, especially super water reducers, will allow the flow of the
concrete to be much higher with the use of less water or for the same flow,
reduce the water significantly. Now you can also get plastic fibers mixed
with the concrete that will help to reduce any cracking by providing some
small scale reinforcement of the surfaces, don't use it to replace the real
steel reinforcement.

Sorry for the length of the dissertation, but I felt a complete answer
required this. Hope it helps.

--
RichToyBox
http://www.geocities.com/richtoybox/pondintro.html
Zone 7A/B Virginia
"MLF" wrote in message
...

The first pond I had was a garden pond, about 12'x6' made of brick and
lined with concrete. It came with the house. It worked well for so small a
pond, and the fishes and frogs and plants liked it.

I wonder if any of you have suggestions for concrete. There are a
multitude of types and additives. However, I would like to know exactly
what type is recommended for lining a pond. And what additives to avoid.


Michael
New Orleans, Louisiana USA
================================================== ==============

You can also acid wash the surface or acid bathe the pond for a bit to
speed up the process.

Jim

RichToyBox wrote:
Concrete, whether truck mixed or gunnite/shotcrete is made of Portland
Cement, sand, water, coarse aggregate (gravel or crushed stone) and
admixtures. The sand, water and coarse aggregates should not pose any
problems. Most of the admixtures are used in such small quantities and are
bound in the concrete, so I don't see a problem with them, either.

You seem quite knowledgeable about concrete, so if you'll allow me I
have a couple of questions.

I have a plastered Shotcrete diving pool built in '87. Planning to
convert it to a swimming pond with fish. Plan to raise the 8.5' deep
end to 4' with dirt overpoured with concrete.

1) Do I need to take off the plaster around the sides, so the new
concrete floor edges mate with the old Shotcrete?

2) Will I need to tie in the floor re-bar to the old wall's re-bar or
even use re-bar in the new floor at all.

3) For fish, do I need to coat the old plaster and new concrete floor
with Epoxy or will normal pool paint do?

Chip