Simmons,

Did you do a cleaning of the leaves and stuff out of the pond before you
shut the pond down for the winter. If not,it is possible that you water is
becoming toxic to your fish because of crap on the bottom decaying. You
need a couple of airstones, and appropriate length of tubing and an
inexpensive air pump. Hook up the air pump to tubing and place the
airstones about 8 inches below the water surface and start it running. A
one or two outlet air pump is sufficient and leave it running for the rest
of the winter 24/7.

Good luck.

HTH

Tom L.L.
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"Simmons" wrote in message
...
I have a large pond (3500 gallons) that has been home to a dozen koi for
the last 8 years. I closed it up at the end of October (Massachusetts) and
for the last two days the fish have been at the top of the water gasping for
air. I have never run into this problem before and was hoping someone here
might have a reason for it and a solution to the problem.

I have a deicer running 24/7 which leaves a good portion of the surface
open. (No other pumps are running) The last few weeks have been brutally
cold (below zero at times) and last few days have been in the high 20's.


Any suggestions why the fish would be doing this?