Concrete is alkaline by its ingredients. This raises the pH of the pond
water. In a fresh concrete pond, the water get too bitter for fish and
plants. Washing the new concrete pond reduces the bitterness, enough for
the fish and plants to tolerate. A little junk of new concrete does not
affect Water Quality much, since people here have hugh ponds. Also, us
ponders have plenty of plants in our ponds. We have lots of organic
matter in them. This tend to lower the pH. A little fresh junk of
concrete is of little concern to us.

If you put a junk of fresh concrete in a small pond, you need to wash
the concrete with acidic solution first. This would reduce the effect
concrete has on WQ.

G-Hoch wrote:

A couple of years ago I made a base for a water lily spitter out of
quick-crete but I heard that you shouldn't put quik-crete in a pond.
What is the difinitive, once and for all answer to this question. I
say where someone was making an underwater light with quickcrete and
no one questioned.

P.S. How do you spell quikcrete?

Well, I *thought* I knew how to spell it until you tossed a few options out
there, and then I didn't know any more! GBG But to answer your primary
question (I think): it needs to be aged over 30 days or so to ensure that
it's "cured". Then you can acid wash it with muriatic acid, rinse, and it
should be OK. Alternatively, you can seal it with a concrete sealer or
paint it with one of those rubberized paints to seal it. All of the above
will keep it from leaching into your pond, which I assume is the is the
underlying question to your primary question . . . G!

Lee

"G-Hoch" wrote in message
om...
A couple of years ago I made a base for a water lily spitter out of
quick-crete but I heard that you shouldn't put quik-crete in a pond.
What is the difinitive, once and for all answer to this question. I
say where someone was making an underwater light with quickcrete and
no one questioned.

P.S. How do you spell quikcrete?

On 15 Apr 2004 08:11:47 -0700, (G-Hoch)
wrote:

A couple of years ago I made a base for a water lily spitter out of
quick-crete but I heard that you shouldn't put quik-crete in a pond.
What is the difinitive, once and for all answer to this question. I
say where someone was making an underwater light with quickcrete and
no one questioned.

P.S. How do you spell quikcrete?

http://www.reboysupply.com/quikrete_products.htm

The concrete answer to your question is relative to the amount of
water and concrete. The danger is in the type of lime used in
concrete. In excessive amounts it can cause the pH to rise as high
as 12. A concrete pond is treated, or coated prior to adding fish to
avoid this happening, smaller amounts of concrete are often used in
ponds without problems. To be on the safe side, one could wash the
concrete piece down with an acid solution like is used for cleaning
bricks. I have a concrete liner behind my waterfall and wouldn't
hesitate to make a light weight using quikrete and cure it before
putting it in the pond.

Regards,

Hal