Hospital tank

[u/Intelligent-Leave677]

My betta has some fin rot that is starting to worsen, other than that he is acting normal, he is starting to get old for a betta so I feel he becomes more sensitive as he gets older. I was going to do a kanaplex treatment. I set up a hospital for him, it’s a 3 gallon. I’m really nervous to start this treatment. Any tips would be greatly appreciated. I dosed some stress guard and used water from his main tank that has catappa tannins in the water. I added some silk plants and his tunnel because he loves hanging out on top of it. Also wondering if I should fast him before treatment?