So my vt, Roy, tail bites or so he used too. I started playing with him with a laser pointer. He loves it. At first at thought he bit because he was in such a small 1g tank. I plan on getting him a 2.5 gallon heated and filtered tank for Christmas. At first I thought he bit because he was cramped. Turns out he was bored. I noticed this morning as I was fixing to feed him that his tail is coming back. Yay! I am still getting him the 2.5 gallon filtered and heater for Christmas. I may even buy a Betta excerise mirror for him as well. I'm super happy that he's letting it grow back now. He's going to start looking like an actual veil tail now! Yay!