tail rot

Hi all! This morning I noticed that my damsel’s tail fin looks like it’s been completely chewed off. It’s a little red around the edges. He’s still swimming and eating just fine. I’m planning on upping feedings until he heals. Do I need to do anything else like treat with antibiotics? I’d...

Hi, first post for me. I have a marine betta that is just beautiful and in perfect shape, until now. His tail has a changed on the edge and it may be injury, or being nipped at. I am most concerned about missing a diagnosis if this is the start of something. It's been 2 days, second day...