I have convict cichlids, and let me just say that they don't take crap from anynody. They have demeaned Oscars twice the females size, and she will defend her rock structure against my 19"Gar, even though she is only about 6". She even gets flustered when my friends get too close to the tank, no fear that's why I love them. Add the babies she just had.....she keeps the gar away, and has kept my 10" pleco from cleaning the glass anywhere near her home. Aggression is her hobby.