I have a male delta fin betta and he's ready for a new tank. I currently have him in a 2.5 gallon glass jar with a spigot at the bottom I use to remove old water. He seemed stressed when I put him in a 10gallon with a filter, so I am trying to keep water currents to a minimum. I am looking at a 3 gallon tank but instead of using it's filter, I was thinking of buying a filter made for a 1 gallon tank to reduce water flow. Has anyone tried this before, or do you have a better suggestion? Thank you for any help!