go with the Hait. cichlid as mentioned above! =] and not with the polleni...if you want all Central...iono but i think Green Terrors are great =] not to aggressive, nice patterns and colorations...you can also go with a Jack Dempsey and a pair of Black Convicts or if you want...just males =] but as also stated above...its better to get species of cichlid from the same region and same temperment and such water chemistry