So I have a male 1 inch betta fish. His name is Royale, or Roy. He's been tail biting for a while now. Roy used to be in a 5 gallon fish tank. I also have a 3 inch male betta fish, Nemo. I moved Nemo into the 5 gallon after his tank bowl cracked and was unable to hold water. Because of this I was unable to to keep Roy in the 5 gallon. I ended up downsizing Roy from a 5 gallon to a 1 gallon. Ever since then Roy has been tail biting. At first I thought it was an injury to the plant I had in the tank. So I removed it and replaced it with a silk plant. There was no way this plant could possibly hurt his tail. Well as Roy's tail kept getting worse I started thinking it was tail rot. I treated his tank for tail rot and that didn't seem to help. That's when I realized it was tail biting. Unfortunently, by the time I realized this more than 60% of his tail was gone. Ever since then, I have put a betta hammock in the tank (which he uses), a cave, and I started playing with him by using a laser pointer and sometimes a mirror. The tank he is in is not filtered, there is no heater (it stays at 78 degrees most of the time), I do 50% water changes at least once a week, and I feed him pellets. Roy is still tail biting. I have run out of ideas on how to get him to stop. Can yall help me get Roy to quit tail biting?