I have had a small yellow molly for about 2 months now. When we bought her, she had a small black speck on her tail - I just thought this was her coloration. However, about 1 month ago a new spot appeared on her side. She was doing fine, no scratching, still eating, swimming normally, etc... so I have just been keeping an eye on her. This morning, I noticed 2 more spots on her (another on her side and one one her top fin) for a total of 4 spots. They are very small and do not seem to bother her at all, but now that they seem to be multiplying more rapidly, I know that it can't just be her coloration, it must be something else. The only odd characteristic with her is that she has not grown at all since the day I bought her. She is still exactly the same size and I would have thought she would have grown at least a little in 2 months.
I have done my research and have read that it could be black spot disease, but I have not read exactly what or how to treat it. I have an anti-parasite medication or an ich medication I could use, but not sure which one would be better.
I just moved her to my hospital tank to be on the safe side though. For now, I plan on just keeping an eye on her to see if more spots develop. If so, does anyone have any suggestions on how to treat it? None of the other fish in my main tank have developed any of these black spots.
Nitrite - 0
Nitrate - 5
PH - 7.6
Ammonia - 0