I have a green BTA that split like that all the time, I have had it for three years and it has split probably 10 times. I give them away and try to keep it down to just one since they get the size of a dinner plate and end up taking up the whole tank. A few weeks ago it spit from one to four. I never feed it and the water quality is fine, I have a lot of sps in the tank that do great., So I know it's just what it does. I also have a red BTA that has split only three times in three years.
So to answer your question if you keep them they will probably take over your tank.