I have a fish that was getting picked on so I moved him to the only tank I could at this time which is basically a grow out tank for my BNP's. It currently has 9 BNP's that are between 1"-2" long, plus a Mbamba Bay that is about 2.5" long. The fish that I just moved to that tank has a spot on his side from being beat up that has some white fluff on it (start of fungus I'm guessing). He seems okay other than that so I want to pick up something to treat him tomorrow morning. What would be a medication I can use for the fungus that would not harm the other smaller fish in the tank?