playing or fighting

I have a small sized pond (1000 litres) with 3 goldfish (1 comet, 1
ordinary abd 1 shubunchkin) and 6 golden orfs.

They seem to hide on a regular basis underneath the waterfall and come
out when i turn on the underwater lights to feed them after 9pm.

They all seem a lot more active at this time. I've also noticed the
shubunchkin seems to follow the other fish around a lot. Either this is
in play or fight, I'm not sure. It looks like he's nippling at they're
tails most of the time.

Obviously, I'm unsure of the sex of the fish, how can you tell?

many thanks in advance




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AlecTPR