Seems like a silly question, I know. 2 gal. tank, filter, heater, light, 1 artificial plant, 1 live plant Betta is sole occupant. I've been leaving my guy alone for long weekends over the Christmas season and I've noticed his tail has been aggressively cropped. It used to be more than an inch long, and now it's down to a half inch. Pretty neatly trimmed too, not ragged. It does not look like any kind of rot. His other fins are OK, in particular his anal fin is still full-length. There are no other fish in the tank. Is it possible he's been nipping at his own tail due to hunger?