Clown Fish Sick?

There’s something wrong with my male clownfish and I’m not sure what. Swim bladder issue maybe? He’s breathing fast and tends to swim very vertically or horizontally against the wall. I did notice white stringy poop this morning but I’m not sure if that’s the problem. The interesting thing is he’s hungry and tries to eat when I feed him (see video) but it’s like he cant see the food. I’ve had him for about 4 months with a female (mated pair) and they’ve been a pair for 6 years. Any thoughts?