My fire eel has gone blind and im at a bit of a loss as to how? It started off in one eye the pupil went white. I assumed it bumped into something in the tank and it got a bit infected anyways my water was perfect and I carried on with 2x wc a week then I noticed today both eyes are white and he is blind. It all a bit odd, all other fish are 100% fine no problems water is perfect. Any ideas on what it could be or what has caused it?

