I know bettas that bite their tails drive their owners insane, but he'll stop before it gets too short, and it'll grow back. Are you making him flare? Are you increasing water changes? have you tried putting different things around his tank? These things take patience and a lot of time, but hopefully he'll stop tail biting. It took my betta a looooong time before he quit, I'm not sure what I did right, but after a while he stopped and then his tail grew pretty again. I'm not sure if you noticed, but my avatar was him after he stopped tail biting and his tail was halfway healed.
Last edited by JKfish; 11-15-2010 at 04:54 PM.