I added a big fat black moor, about 5 inches long, to my 55 gallon tank with my calico orandas. The tank has a few plants and some fake rocks. Today I noticed that one of my black moor's eyes is gone! It seems to have popped or something. He is swimming funny (kinda sideways) but he is still eating. I added some MelaFix in case it's infected. Is he going to be okay?