Sick Betta

[Yash]

I was at my buddies house today and he has a blue Betta fish he has had for over 2 years. Today he noticed that one of the bettas eye was bulging out, larger then the other one. He's not sure what it is but I told him someone on here had to know. I have attached a photo. Let me know what you guys think.

 

[GuppyLover]

It looks like pop-eye, which is usually caused by bad water quality. Someone else should be able to tell you about treatment.