[leftfish]

I don't know if it was nipping or a fin rot that caused equal shortening of my black calvus's pectoral fins. They are half the length of what's normal and causes him to wobble as he swims. he's a year and a half old and about 2 inches. Is there any treatment needed (it's been like this a while and no one else in the tank has any problems) or can I expect his fins to grow back to full size eventually?

Thanks, Dan

 

[Robin]

They should grow back Dan in ideal conditions. It sounds like fin rot. I would first of all test your water and then regardless of the readings do a 30% partial water change with a good quality dechlorinator and siphon the gravel. If there is ongoing aggression in the tank then I would remove this fish to a hospital tank so that his fins have a chance to get better--the stress of the aggression and the continued nipping will make it hard for him to heal and unfortunately once a fish has a 'soft spot' the other fish will tend to pick at it.
If he seems healthy otherwise then give him a week in the hospital tank to see if the fins recover on their own. You can treat with Melafix. If they don't respond or seem to be getting worse, and/or the fish stops eating then you'll need to treat with an anti-bacterial. See what's available at your local fish store.

Robin