RTC standing straight on tail

[Nikhil b]

I have 10” red tail catfish it was ok till evening from past 4 hrs it’s behaving weird like it’s standing on its tail vertically can any one help I changed 30% water now am worried as it’s my favourite fish and don’t want to loose him he didn’t eat since 5 days and now it got some little bump in belly

 

[tlindsey]

I have 10” red tail catfish it was ok till evening from past 4 hrs it’s behaving weird like it’s standing on its tail vertically can any one help I changed 30% water now am worried as it’s my favourite fish and don’t want to loose him he didn’t eat since 5 days and now it got some little bump in belly

If possible post a pic.