Ok.. So I need some guidance as to what I am doing wrong.
Mt. T has slit fins, which I presume is fin rot.
I change his water religiously 50% every week, I have it calendared. And I rinse the filter out with each water change and change the filter monthly. He is in an Aqueon 2.5 Gal Tank, heated with a 25 watt Elite mini-submersible 5.
The girl who gave me the fish, who also has one, hers stays in an unheated 1/2 g bowl on her desk and I have to fuss at her to change his water. Her fish is never sick..
What am I doing wrong?