I like Severums better but I'd do 2 female Cons before I'd do a male/female Severum. A Severum pair in a 120 g with an Oscar probably wouldn't go over well. Convict females are really pretty. Their fins get teal and blue and green and they've got those red stomachs. Stay small and quick enough to get away from an Oscar. If I keep typing I may just have to set up another tank of female Cons.......

