"Ed Hayes" wrote in message
...

We are going to install a small pond in our backyard.
It will be one of those bio-eco systems that do not require massive
filters and chemicals.
Town code states it can't be over (I think) 18 inches without a fence
around the properity or pond.
We don't want the fence so we want to keep it to a max depth of 18
inches.
These bio-eco systems require fish and I am not sure 18 inches is deep
enough to protect them in our cold winters here on Long Island.
Any ideas or thoughts?


18" isn't really deep enough for Koi. Goldfish will be fine as long as the
normal freeze depth for your area isn't over 5-6" BUT you will still have to
open the pond once a week or the trapped gases from decomposing vegetation
will kill the fish.

You can buy a floating heater that is safe for plastic ponds. It is
actually called a livestock water trough heater. It pulls about 1200 watts
on a continuous load once the water temp drops below 32 degrees. It might
be cheaper to buy new fish each spring. This thing is about 6" around an
will maintain an opening of about 18".

Contrary to what another poster said, you should not run your pump once the
water starts to freeze as that messes with the thermal layers and can lower
the overall water temp.

The advice to check with local pond supply or landscape services companies
is an excellent one as they will know far more about your area than any of
us do.

Would be happy to exchange public or private postings about your pond.
Getting the correct balance in the eco-system can be a challenge. There is
not one way only to do it. It is a combination of the ingredients.


Colbyt