in my 10 gal, i have one male betta and one mystery snail. people complain about how dirty mystery snails can be, but i love mine. he's fun to watch. particularly when he's eating. i may add some cherry or ghost shrimp in later. they SHOULD be able to work together. they may not though. that's the risk you take when you put anything in with a betta. other people have suggested other types of snails, otos, and cories. I've even heard of people having success with guppies and mollies. Though that's a big risk one takes. They are pretty showy and nippy! of course, you could always do the sorority. i've heard people say that a person new to fish or new to bettas shouldn't try a sorority right off. just some stuff to think about. good luck!!