Sodapop just can't catch a break. He's had ongoing tail biting issues for some time now, but he stopped over the last month or two and I hoped that was the end of it. But just now, I went to feed him, and he came to the surface, spun around quickly... and a huge chunk of his tail just fell off and sank to the bottom of the tank.
I freaked out, grabbed the net and fished it out, and it was about 1.5cm long and half a centimetre wide... the hole in his tail now almost reaches his body. What the heck? There's not way he could have bitten it out neatly, the cut is almost a perfect rectangle. D: D: His water is fine, I changed it (50%) two days ago, and it's cycled. Heated 5gal. What the heck could have caused this? There's nothing sharp in his tank and the filter is well baffled and on a low setting.
He was just starting to look pretty again. *sigh*
Should I pop him in AQ salt for a day or two, just in case of infection? He ended up with septicaemia last time he tailbit, so I'm nervous about it now.