bottikoferi, i had one for a long time. he was a terror. They are much less aggressive at small sizes like yours, but when they get to about 10 inches or more they begin preparing to breed. they will rearange your tank substrate to resemble a mountain on one side and at this point they will kill anything else smaller than them. They are illegal in many states because they are catigorised as tilapia and states worry about them getting big, people releasing them, and they could survive (even strive) in many north american waterways. Id say try to get rid of him as he wont enjoy the high PH of your africans, and DONT release him if you find your LFS wont accept him. good luck.