well not sure if this problem is just temporary because I just mixed them and my rather larger cichlid chased my new additional cichlid around for hours.. the larger cichlid started turning white (he was black with white stripes b4) and his back fin started to get very tense and was slicked back... he started chasing my new cichlid around but not in a very aggresive way but maybe in a more sexual way , could that be what he's tryin to do?