Betta Fish: What’s wrong with my bettas fin? It was a small white dot this morning now that white dot has gotten bigger.

Is it fuzzy?

I’ve had this problem twice once in a female I’ve had for 9 months and wasn’t able to save it and then again from a petco bumble bee I had got two day after in my quarantine. Best I could figure was cotton wool disease or columnirus not sore that’s how it is spelt it seems like hit and miss on curing it. I used methylene blur baths twice a day and kanaplex. Best I can figure is bacterial infection that a fungus attacks. YouTube Father Fish and columnirus disease I think if I would have followed his advice right off they may have made it. I hope your guy does!