No problem. You could try adding some snails or shrimp to your tank to eat algae. Although it sounds like your betta is rather aggressive- so you may want a backup plan. Ghost shrimp don't eat algae, but they cost about 10 cents, so you could get one to see if he got along OK with your betta. If you, so could get the more expensive, prettier, algae eating shrimp such as a Red Cherry Shrimp.