I have a farm where i raise the common african catfish called Clarias gariepinus. It is a profitable business like most legitimate businesses.
Proper preparation prevents poor performance, so be prepared before you get into any business fish farming inclusive.
You can post your questions on nairaland and i will attempt to answer.
I will not tell you that you will be raking milllions but if you have your own farm you can live a very very comfortable life.
You can also contanct me through my email greenaquaculture@gmail.com.