You can put Peacocks/Haps in the same tank, however, do not put MBUNA or tangs in the same tank as a beginner...
Usually, I would discourage peacocks in with a hap tank b/c they don't thrive, but, if you can get them as big as the haps then they will become one of the dominant fish in the tank. It is all about pecking order in a "male" tank.. You want everyone to feel comfortable to show off their natural colors. This is usually best done in bigger tanks 125+ so if you are going to do a 55g tank I suggest at tops 10 different fish b/c they only have about 3 foot to swim in.. The number one rule to keeping african cichlids is to have a LONG tank, depth really doesn't matter, but length is where you will see the different personalities. Hope this helps.
Usually, I would discourage peacocks in with a hap tank b/c they don't thrive, but, if you can get them as big as the haps then they will become one of the dominant fish in the tank. It is all about pecking order in a "male" tank.. You want everyone to feel comfortable to show off their natural colors. This is usually best done in bigger tanks 125+ so if you are going to do a 55g tank I suggest at tops 10 different fish b/c they only have about 3 foot to swim in.. The number one rule to keeping african cichlids is to have a LONG tank, depth really doesn't matter, but length is where you will see the different personalities. Hope this helps.