I have a group of eight young from Jose that I'm growing out. When I got them about 4 months ago, they were about 3/4". Now they're getting close to 3" and they really like to interact (i.e.chase one another). No real damage at all ... just very competitive, especially when it comes to feeding. Even more so than my 'polleni'. They are like little pigs. The pecking order is already being established at this young age. I really believe it's important to let the young Madagascans grow up together in order to develop a long term stability in the group.