"MC" wrote in message
om...
I had a pond deicer last year. It didn't work in Chicago. I wound up
having to bring the fish in at the last minute. Also, I believe
Chicago is too cold for a pond of my depth without a heater. A decicer
does nothing to the water temperature at the bottom of the pond where
the fish are. Koi do not hibernate. Ultra cold water is not good for
them.


That is why ponds should be dug to at least six inches below the frost line - to
insure that they don't freeze completely solid. As for ultra cold water, I
don't know what you mean by this, as water freezes at 32 F. My pond, with a
de-icer, only had about 1/16th of an inch of ice on if for about two days last
year, and that was only at one end of the pond. The water below the surface
never got below 39 degrees, and my Koi, goldfish, and channel catfish all did
just fine. I didn't lose any fish at all. My pond is 45" deep (18" above
ground, 27" below), while the frost line here in Louisville is at 22". Koi will
stop eating below a certain temperature (some say below 50-54 degrees F). Mine
stopped eating below 50 F. So while they may not hibernate in the sense that a
bear will hibernate, they do become lethargic, and greatly reduce their
activity. This is normal behavior for temperate fish in winter.


"George" wrote in message
...
"MC" wrote in message
om...
After much research, I've decided to use solar bubble wrap pool cover
floated on the top of my pond and a titanium tube-style heater. The
pool cover will have a border of about an inch to allow gases to
escape. My questions a

1) How do you use one of these acquarium-type heaters? I would imagine
it would burn the pond liner if I just throw it in there. If I suspend
it, I would be concerned of it getting knocked loose. Do I need a
wire/mesh case to keep the fish from burning themselves?

2) I've read bio filters are useless below 50 degree. So I won't run
it. Is it better to remove it from the pond, or just leave it? I
anticipate the heater will keep my pond around 40. I don't intend on
"heating" it, just keeping it from freezing solid.



FYI: I am in zone 5, 500 gallons, 30" deep, 6 Koi

You'd have to have one hell of an aquarium heater to do the job you are
asking
of it. On the other hand, there are products out there that do the job more
efficiently. I use a pond de-icer. It only raises the temperature at the
surface to a level that will keep most of the pond ice-free, so it isn't on
all
the time, and saves on the electrical bill. Check out this web page for more
information on pond de-icers:

http://www.pondsolutions.com/pond-heaters.htm

The one I have is the green one.

Good luck.