Goldfish, KOI, catfish, bass, etc are not
coldwater fish; they are designated as warmwater
fish. Just because they can survive under ice
doesn't make them coldwater fish. Examples of
coldwater fish are certain varieties of trout,
salmon, etc. These fish live, frolic and breed in
water temperatures from 40-60 degrees. In fact
sixty degree water is warm to them.

The designation for fish is coldwater, warmwater
and tropical water. Goldfish and KOI could
possibly be designated as coolwater fish, but this
is not really designation.

Tom L.L.
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"claude rogers" wrote in message
...
There are other cold water fish you can keep
instead of goldfish and koi,
but it is not recommended to mix them. Catfish,
bluegill, bass, regular
type pond fish or game fish I believe they are
called, unfortunately they
don't show up very well in a green "algae"or
black bottom pond and they tend
to eat goldies as they get bigger, not always,
some people even on here keep
catfish in their ponds with their koi and
goldies. I was very tempted to
get a small catfish until I was warned that I
would end up with no goldies
left and a very big and full catfish.