Agreed, definitely no goldfish! You can try Corydora catfish, I had 4 in a ten gallon with my male Betta. They need to be in groups of at least 4. Amano shrimp and snails are a good idea too. Amanos are a bigger shrimp and don't die off within a week like most ghost shrimp do. And since they're bigger bettas don't usually see them as a food source (USUALLY!). They also clean up the algae VERY well. I had a slight algae problem and they cleaned up the tank in a week (with just 4 of them!) Snails are okay but they also produce a lot of waste and some can reproduce very fast. Mystery snails are usually colorful and pretty, so maybe one or two in your tank would be okay. I've heard guppies can be kept with some bettas, but all bettas are different. You really just need to see if he will be aggressive or not once you put them in there.
Last edited by Viva; 07-05-2013 at 04:06 PM.