ive just come home and found that my cory has one eye hanging out and the other one bulging out. he was perfectly fine yesterday but has suddenly developed this. he is still swimming about a bit and apart from this seems healthy although his fins are quite tatty as one of the other fish has been attacking him. what can i do? i know i cant save the eye thats hanging out but can he survive with one eye? what can i do to try and treat it or is it just kinder to let him go and put him out of his pain. im so upset hes 2 and a half years old and he was from my first lot of fish.