# Knob on my Black Cal



## Sheff (Aug 27, 2013)

*Knob on my Black Calvus*

Hello
I just found a know type thing on the side of my Black Calvus. He is one of 4 in a 60 gal tank with a few fairly sharp rocks. None of the other fish have any signs of any issues and this guys thing just appeared today. I tested the water parameters and although the nitrate level may be slightly elevated (20-30) it would certainly not account for this. I see them bite each other off and on on their sides but again I've never seen anything like this. It's like a whitish mole.
Any help would be greatly appreciated


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