I have an algae problem in my fresh water tank, what fish should I buy?

My tank is 10 gallons. I have one male betta and 3 white clouds in the tank. I have a soft algae problem. But I don't want to put algae-killer in the tank, because I have a decorative algae ball made of hair algae. I was thinking of putting two of the offspring from our albino corys (from our other tank) in there. Would the corys work? I was also considering a cherry shrimp, but I think the betta will try to eat it. I don't want snails, because most snail breeds are dual gendered and that leads to snail population problems. Do you have any suggestions? Thanks!