I had 6 discus about 2inches. After several months one of them got very skiddish would swim very fast bouncing of the glass. A day
or to later it was dead behind the heater. A month later the same thing again. In less than a year all had died the same way. What do you think happened? I don’t want to buy more fish just to loose them again.
The fish is attacked by bacteria and parasites.
The fish feels irritated and itchy.
She will try to rub on any hard objects.
If no medication is applied, until they attack the gills, the fish will die instantly because of suffocating. Or the fish will get stressed and fall sick.