Keep mine in 2.5G tank with 0.5 in. deep natural gravel (not plastic coated) for hosting denitrifying bacteria. A couple Anubias left floating in tank provide a place for Betta to rest and decor. Do 25% water change once a week vacuuming water with small gravel cleaner and replace with same temperature dechlorinated tap. Feed Hikari Betta pellets (4 or so) and a couple wingless fruit flies (from dart frog food cultures) daily. That's about it .