"Greg" wrote in message
| I have a pond with Koi and goldfish who lived happily together
| for a few years.
| Today however all the fish apart from the large Koi ganged up on
| another goldfish and seemed to be trying to push it out of the water.
| They were quite ferocious in their attempts.

Hello Greg,

I'm in the UK too, new to ponds (2 months) and have only 2 goldfish
in a small tub 24"Hx12"D. We had no intention of keeping fish but
were advised by the garden pond centre to put them in with the water
lily, so that they would eat mosquito larvae and small worms that had
infested the water. Breeding behaviour began immediately as the fish,
Pip + Pop, chased each other around their new home.

The lily had stopped growing after all new shoots were eaten by pigeons
that perched on the side of the tub. We put a grid over the tub but it
was too late for the lily, so, after cleaning the pond, we now have only
fish and oxygenating plants.

In their new surroundings P+P returned to their courting with ardour and
I was keeping an hourly check on them. At 11pm on Saturday I was
shocked to see one of the fish lying on the lawn about a yard from the
pond. Fortunately, it was still alive, had no sign of injury but when returned
to the pond the male began pushing her around the pond sideways. I can
only assume that she jumped to try and escape his advances.

We separated them for a day, then returned the male. They have calmed
down but I’m still keeping an eye on Pip so that she doesn’t make another
leap for freedom. I haven't seen any eggs but then I understand that they
would eat them anyway.

Pauline