Black Moor

[harveys-3]

I've had the same group of fish for about a year now, and have never really had any problems.
Recently, within the last few days the 2 bigger goldfish, one being a lemon goldfish not sure of the other, seem to have been chasing the largest black moor and he seems to be a little distressed and has actually ripped his tailfin.
Anybody got any suggestions why they have started doing this?

[harveys-3]

It's the fish on the left that seem to keep chasing the black moor. They sometimes also chase the other fish, but no where near as much as they do the black moor.

[janislovesfish]

Goldfishes, when they mature, tend to become more territorial and aggressive. The reason why the blackmoor is the one being constantly chased is because it swims slower. Seeing your other fishes, I know they are faster swimmers. :] If this continues, what you can do is separate them. You have to provide a separate tank for whichever you choose to transfer.

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