Contrary to popular belief, betta fish can live with other fish as long as only one male betta is in the tank. If two male bettas are housed together, they fight.
A male betta can be housed happily with female bettas or other fish species. Female bettas can share a tank with female bettas as well as with other species. Caution should be used when housing bettas with companions as some species of fish love to nip at male bettas' long fins. For this reason, bettas should only be housed with peaceful fish. Guppies, mollies and platies make good companions for bettas whereas fancy goldfish, brackish fish and pond fish are best avoided.