I have had my cbb for 2 years. I recently noticed that she re gills appear red and maybe swollen. She does seem to be breathing faster too. She does eat normally and doesn't appear to have any other lesions on her. My tank is well established, over 3 years, and her tank mates don't display any problems.
I did test for ammonia, and it was zero. I do tend to run nitrates though, around 40.
Any advice appreciated