A photomontage of a Grouper in the forest. I can't think of anything else to say about the composition, so let me tell you about groupers. Grouper are fish of any of a number of genera in the subfamily Epinephelinae of the family Serranidae, in the order Perciformes. Not all serranids are called "groupers", also included in the family are Sea Bass. They may reach extremely large sizes, growing to lengths up to 2.5 m and can weigh as much as 360 kg.