It's an Aqueon Mini Bow Filter (120 volts, 60 hz). It came with the tank. I haven't had to change the water yet because I just set the tank up but I'll do a cleaning Friday. I tried crushing the pellets and he ignores them. I tried again with a plain pellet and he grabbed it and spit it back out. He completely ignores flakes and turns up his nose at worms put directly in front of him. This is completely beyond me! I've never met a betta who won't eat at least ONE kind of food I have!
Pet lover: experience with--rabbits, dogs, guinea pigs, snakes, fish, hedgehogs, hamsters, and horses.