A lot of people think they split when something is changed in the tank, especially after it being the same for a length of time. So flow, direction of flow, possibly rockscaping, parameters, etc... No need to move the other one, I know my greens actually stay fairly close to eachother. If you don't regularly feed, maybe keep an eye on each of them and make sure they continue to look healthy. If not feed them. Do you have any pics?
