How big is the tank? I'm not a fish expert, that's my da, but if mollies or guppies have flashy fins/are fins nippers, then they can't be housed together. If they're not flashy or nippers, then they can, as long as the tank is large enough.
~To those who say that betta's can't be housed with other fish~
That's a lie. I have my betta with another fish in my 10 gal. as I type. They make great community fish, as long as the other fish don't have flashy fins or are fin nippers.
