I have a skinny platy in QT
(see sig). I don't know if it's TB or wasting disease, or something else. She's been skinny like that for months now - at least 2 1/2 months anyway. She had fry, then just kept getting skinnier and skinnier. I have got opinions from all the LFS
around here, and tried everything available (antibiotics, medicated food...). The good news is, she hasn't gotten skinnier in the past month. But she doesn't look normal yet either. Right now I'm trying Hexamit (?) and I've just finished the first course - they say to do the 3-day treatment 3 times.
I thought about putting her down too, and I probably would have if I thought she was suffering. She behaves normally, and other than the fact that she's a little hollow-bellied, and that I've spent probably $65+ for meds on this little $3 fish, she seems okay.