Hello, my betta recently just recovered from fin rot and has been doing well. However, today after I went out for a bit when I came back he injured himself. Nothing is sharp in his 10 gallons tank and no other fish either. On the side of his body, it looks like he rob himself against something and as a result, he damaged his scale. His side body looks like someone scratched your car. I wonder if anyone know why this is happen? I wonder if it is because he sees too much reflection of himself.