That depends on the size of your tank, really. I have some peppered Cory cats and they're really good fish that don't easily catch diseases. However, if you don't keep the tank pristine, they live on the bottom of the tank, so they can die from pollution real fast. Make sure you have lots of hiding places because they're sensitive to light. Also, if you don't at least keep 5 or 6 they get shy and you won't see them that often. They do okay in pairs, so it's not as if you can't get them in smaller numbers. Just make sure you get at least 2.