In my opinion, the #1 best betta tank is the 6.6 gallon bookshelf aquarium. It's not too expensive, and has the perfect dimensions for a really natural movement (long and shallow, closest to natural betta habitat).
I would add to that list:
- Garlic Guard or any pure organic minced garlic w/ juice
- TetraAqua SafeStart water conditioner with stress coat
- Hikari Freeze-Dried Blood Worms (should soak in water before feeding, 2-5 worms per betta as a meal)
I'm a huge fan of the Biowheel water filters, but for bettas you really have to turn the flow down, the smallest one I can find is for 20+ gallons and it's quite powerful. Really, really good filters, and good for quickly starting bacteria seeds for new tanks, too.
