Still struggling with my betta and fin rot --- need advice

[Odd Duck]

Neomycin is fine as a first line against Gram negative bacteria, but Kanamycin (Kanaplex) is going to be my first choice when infection is invading the body vs just the fins.

I suspect since Goldie Blue had such a severe infection that invaded deep into the tissue of his tail, that it will take longer for all the affects to clear.  Everything looks and sounds like he is doing better, so I would keep up with excellent tank maintenance, aquarium salt at 1 tablespoon per 3 gallons, and tannins whether you do it with IAL’s or rooibos tea or even oak tannins or a combo of those sources, with a goal of at least a light tint to the water.  The IAL’s are the only ones supported by any studies (not really terrific, double blinded studies or anything) but I’ve also used oak leaves and rooibos tea and had apparently similar effects anecdotally.

Unless Goldie Blue gets suddenly worse, I would continue the current plan since he seems to be responding well, finally.