I'm not sure how this is suppost to work let me tell you i have (had) a GSM (3" or so)by its self for about 3 months it was doing real good. now i bought another (1" or so) and he is noticably smaller well the big one beats on the little one only when he gets near either one of the 2 sea anemones. Other than that the little one dances and shakes for the bigger one. but no real bond yet only been 3 days now