Join Date: Jun 2010
Location: Northern Virginia
You could get some ghost shrimp, but be aware that bettas are carnivorous and see shrimp as prey animals. It is inevitable that the shrimp would eventually get eaten by the betta, even larger ones. The betta will peck at them until they succumb and then rip them up--if you don't want your betta's tankmates to get eaten, I recommend pygmy cories.
Pygmy cories are the smallest species of corydoras catfish available, so you can fit more into your tank than you would if you chose a different species. This is important because a 10G doesn't give us much stocking space to work with and cories are a social schooling fish that swims in schools of hundreds to thousands of individuals in the wild. The more individuals you can fit into the tank, the happier they would be. In a 10G, you could fit 6-8 of these guys--but not all at once. Two at a time every week or so should be sufficient--you need to add them slowly because the bacterial colony in your filter is only sufficient to support your betta at the moment, if you threw all of them in at once you'd get ammonia spikes. Introducing the new fish slowly will give the bacteria colony time to grow and compensate for the new additions. Hope that helps.