so.. i'd never had a pet fish till a few months ago. i got a betta and a bowl and he's doing just fine. i am looking to expand a bit. i want to put him in a bigger tank with a filter and some other fish. nothing big, just like a 12gallon tank or so.

how many, and what kinds of fish can i put in a 12 gallon tank with one male betta? i dont know much about this crap so try and bear with me. thx