A few days ago a bought a brand new betta. He's a veiltail, but I think he's one of those giant bettas, as hes HUGE. Anyway, he was fine a few days ago, and he was fine last night. I was treating him with melafix, just because when I get a new fish I put a drop into my tank to cure any lurking bacteria. He was fine last night, but this morning I woke up and his back fin is completely SHREDDED.
I think he may have gotten stuck by the airstone because the airstone is in a huge tube with an open top. I think he may have swam down the tube and then the airstone destroyed his fin. I'm not sure. I added more melafix to the water, and I am planning on getting a new tank for him today. What should I do?! Can fin rot develp overnight? I JUST changed the water 2 days ago, so I know he's not due for a water change! I feel so bad for my new guy, and he was doing great until just now.
Any help would be great! Thanks!