Grouper (Epinephelussp) is large. They like quiet, are afraid of waves, like warm, are afraid of cold, like clear, are afraid of turbidity, so they like to live in the reef cave and coral zone. They are also the top predators of coral reef system, most of which are carnivorous. Most groupers are solitary, and generally do not gather except during the breeding period. Groupers have big mouths, which enables them to inhale a large amount of water in a very short time to form negative pressure, and then suck prey into their mouths. Grouper has a special feature is hermaphrodite, with sex transition characteristics. It matures as a female firstly and becomes a male a year or a few years later after gives birth to its baby. There are also groupers that convert directly to males as juveniles. What you see here is a Gentian grouper (Epinephelus lanceolatus), which is about 1.2 meters long and weighs about 100 kilograms.