I have a tank under quarantine for ich, with loaches, baby jurupari, and a bgk. THe loaches and the knife looked fine throughout the treatment, but just recently I noticed something weird. Their are white areas on my knife's side, like he is losing color. I have seen bacterial infections before, but it doesn't look like that. He is also acting odd (swimming upright, not usual hiding behavior). He isn't looking sick yet, just showing those telltale signs that something might not be right. All my sick fish are recovering fine, I don't know why he suddenly seems to have gotten worse. What do you think.