Hello and welcome to the forums. There is a specific forum for information about compatibility between species and what conditions you would need to take into consideration when adding a Betta fish with companions. I would suggest asking there for specific information about caring for the other species as well as what volume tank would be good for certain species, in order to take into account bioload.
As for what species are compatible with Betta fish, here is a list of some species that work well: http://bettafishawarenessday.blogspo...tank-myth.html
Do note that they all have different requirements and personalities do not always get along, including that of the Betta fish. My boy, for example, simply will not tolerate anything in his tank even though Betta splendens are known to be compatible with other species.