Yu could always get a female betta they do pretty well with other fish and the betas males do ok with other fish some time just as long as there not fin nipper, colorful and bright
I have a 55 gallón tank with 4 tetras. A red tail, placo, a bala And a sunrise platty. I have a lot of plants. I started with 7 baby tetras when I got home there were only 4 so I caught them and have then in a old 1 gallon betta tank that I had but I've never had baby fish