Zuli, my beta fish started developing early fin rot stages just a few weeks after I got him, I thought the brown at the end of his tail was just because he had been bathing in the brown algae that had been growing. (Btw we have green algae, not brown algae now.) but recently I’ve been seeing that his tail is ragged and more brown now, it’s tail rot. I was crying until my mom found something that will hopefully fix it, we’re going to pick it up! He has also had discoloration and hasn’t wanted much food, and lost his playful, silly, full of energy self. Here it shows an old pic when it just started getting brown and then it shows his tail today :(
Edit: today is his last day on the medicine, he is doing a lot better, he has gained more color back, gained his appetite back, and his tail is less brown and already growing back a bit! I’m so happy this worked.