I had a catfish, acquired in November; he was a small spotted albino hoplo catfish. During a 20% water change, and a small bang he went into a frenzy of swimming upside down, it seemed like his bladder was having issues, and he occasionally stopped then started moving again. He passed away the morning of January 7.
During the water change, we scooped the water out with cups. The water was filtered. He would come to the surface of the tank, and if our hands were clean, we would let him "kiss" them.
His health was not great before the death, however, and he had a minor tumor (which was probably cancer) and cut barbers, which were infected the previous day. Bacteria were growing on them so I scared him (while he was swimming he dropped them). Shortly afterwards they healed, hiding the red blood on his barbers.
He came in November 2020, 3 months ago...
I would like to know how he died. He couldn’t have died from pH levels as it was around 7 on a litmus test. It may have been shock or due to heart paralysis or maybe even the water change. (I did not do the water change, my father did.)
I would like to hear your answers or theories of his death.