It all depends on the ages and sizes of all parties, when introduced to one another. It's very risky, but if you introduce them to one another at a younger age, your chances for success are greater. Also, you do not want to introduce a NEW BGK to a well-established tankful of cichlids. They've probably established their territories and would just pick on your BGK to the point of death. Keep in mind that BGK's have a unique swimming pattern and they often bump into other fish and invade their personal spaces, because they have poor eyesight. An established cichlid has zero tolerance for that type of treatment from another fish.