I have never kept Cichlas, always liked them, but I've always been caught by different projects. Had the Boulengerochromis project failed, I would most likely have filled the 400gal with Cichlas. As it stands, aggression wise, Cichlas are pups compared to the Emperors. Put 6 Emperors together and you have a recipe for destruction, but put 6 Cichlas together and you have a badass tank

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It has been mentioned above the size, girth, attitude, different variants and what not. All I can add is that I cannot wait to get my first group ...whenever that happens.
For those not thinking I'm a hater and are wondering how big my emperors are, the answer is 20"+ male and female wild caughts.