Well lucky for you I bumped into this site and used to study betta's. With the tank I started with a very small plastic one, but I wouldn't recodmend putting any things for the fish to hide in besides a plant in there. With the filter if you don't want to change the tank every week or two i would get one. Betta's come from Thailand and Vietnam they grow up in rice patties, from my studies they do like heaters, but they can be at room temperature as long as the room isn't freezing. Hope this helped!

- I_love_my_pets