Clownfish's eye is puffed up

[erik]

Hello,
I've had a healthy pair of Ocelaris Clownfish for about 5 years.
They've been spawning for almost 3 years and appear very healthy.
I just noticed a few minutes ago that the male's right eye is puffed
way up. It looks cloudy and it's sticking out quite a bit.

He's still eating but he's having a little trouble finding the food so
he must not be seeing out of that eye.

Any ideas?

Erik