White lump on Panda Cory

[kitbasher]

My largest panda cory, just shy of one inch, has a large white lump at the base of his left pectoral fin. The lump is about the size of a bb. It is mostly opaque white, and has a smooth texture. It really looks like some sort of growth under the fish's skin. The fish seems to not be affected too much by it. It continues to swim around in panda cory fashion.

Tank information

The tank is a 55 gallon has been up and running for 2 months or and it was seeded from an cycled 20 gallon.

The water tests at
0 ammonia
0 nitrite
10 to 20 nitrates

and is roughly 79-80 degrees

I do weekly partial water changes of 10 gallons. All water is treated with Prime before it is poured into the tank.

The stocking list:
1 x 5" angel fish (body is the same size as the gold sevrum)
1 x 5" gold sevrum
1 x 5" rainbow shark
1 x 4" clown pleco
3 x 1" panda cory
3 x 1" julii cory
3 x 1" zebra danio

The tank has a ugf and a aquaclear 110. 110 has the foam and the ceramic bio rings. I have not put in the carbon.

Any suggestions? I was going to put him in the qt tank, but my wife is concerned about him going in by himself, the three pandas are always together darting around and playing. Unlike the three julii's which hide almost as much as the pleco.

 

[Devilishturtles]

I would simply observe it. It could be nothing at all (likely a genetic thing) or could be a bacterial issue. Sometimes little things just grow on fish and it's a genetic mishap only. A benign tumor. If it continues to grow or get red, large, white around the edges, I would be concerned for bacterial infection.

As far as QT, IMO you can return him in a few days if there is no change in behavior or attitude, eating habits, etc.

HTH

 

[kitbasher]

more problems with Cory

The white lump cleared up a week or more back. But today this same fish was found floating upside down at the top of the tank. I went for the net and he shot to the bottom of the tank. This morning he was spinning vertically and ended up stuck to the inlet for the aquaclear filter. I have put him in the qt tank. I will watch him for the next few and do some water tests. Have not done any this week.