My Ghost Shrimp has been doing just fine with my male Betta. It's kind of funny, it's almost as though they hang out together. The floating plant my Betta usually stays around has now become the prime chill spot for my shrimp. The Betta actually just stares at him for minutes at a time, and when he gets too close, the ghost shrimp touches him with his antennae and then the Betta moves back. It's quite entertaining.