I’m not a super experienced betta owner and yesterday I got a new betta. I have him in a rimless tank and I absolutely cannot tell if he can see his reflection, but he’s darting up and down the side of the glass on one side of his tank. I tried covering it with paper, rotating the tank, dimming the tank lights, and brightening ones in the room. Nothing seems to help and I’m not sure if that’s even the issue anymore. I’m scared that he’s stressed and I don’t know what to do. I know this isn’t a lot of information but I’ve never seen this behavior before and I’m not sure if it’s urgent. Thanks so much.