I just realised my betta already had early stages of finrot,had dark edges on his fins & he seemed to have taken a bite out of his own tail when i got him. I assumed the dark parts was part of his coloring. He was perfectly fine yesterday(i even posted yesterday about his belly & have photo evidence his tail was okay-ish aside from the dark edges) but today when i woke up there was multiple tears on his tail. I don't know if its fungal, bacterial or just torn from decor?? Right now he seems okay. Im treating him with aquarium salt but im just worried it might be something serious since theres so many tears and already 3-5mm in length. Im scared if it really is bacteria or fungus because they ate his tail up pretty fast since they already did so much damage in ONE night.