In a 180g tank, I don't see any issues, but you never know....Just make sure all the ones you get is smaller then your existing one. That means your existing one will be the dominant female and one of the smaller ones will become the dominant male and all the other little ones would be secondary males. IF your existing female ever dies, the dominant male will become the dominant female and one of the secondary males will become the dominant male. I never kept them like this cause I don't have big enough tank, but I know someone else who have done it, ask Waynesworld, he knows.....For my tank, when I got two baby clowns together, one died at day one for some odd reason. I then replaced one later down the road with a bigger one since mine was pretty small, the bigger one became a female and my little one is the male right now....