|You will need an air pump to drive
your filter. A small one should do the trick. You want to keep the water
moving slowly, but not forcefully. No Betta likes fast, swirling water.
This would be a good choice :
Elite 799 Air Pump
Designed to provide air for one air-driven
item (filter, bubble stone, etc.) in a small aquarium. A noise-dampening
pump cover and base plate prevent pump vibration and movement.
Long-wearing coil and swing arm hinge provide long life.