Poseidon lives alone in a filtered five gallon tank. In his tank I use tap water, conditioner and aquarium salt. Also, if and when I remove him from the tank, I scoop him out with a cup instead of a net to avoid scraping his fins.
A few weeks ago I started noticing what appeared to be tears in his tail. I was hoping the condition would heal and that he may have just torn it. But instead, his condition has gradually gotten much worse, and there are large chunks of his tail missing.
I talked to the Petco manager about this (who did not actually see the fish, but just gave me his advice). He said that if the tail appears to be 'melting' away, or if it has red or white around the cuts that it is something to be concerned about.
His tail doesn't quite appear to be melting...it's more like someone has chopped off the chunks with scissors, leaving very rough-cut edges. There is no red or white anywhere around the cuts, however.
I would post a picture if it were possible, but at the moment I don't have a camera available to use. Does this description sound like tail/fin rot?
If so, what is the next step I should take in order to treat him?