Backyard Aquaponics
A place to discuss aquaponics

This looks a bit odd to me. On the largest fantail goldfish I have looks like there was a section taken out of both fins in the same spot. Not sure if this might be from stress illness or pestering fish. There are 2 large fantail goldfish and 7 small feeder goldfish in the tank. Small ones don't really mess with the larger goldfish and just get the hell out of the way.

I wouldn't worry about it.

They'll nip at each other, or it might have gotten caught on something.

Goldfish are pretty easy going, they won't do much damage.

Like I was saying it looks odd. Same spot on both fins. Mostly posting out of it being odd.