Potato groupers (Epinephelus tukula) are some of the largest predators in the coral reefs of the Indo-Pacific, reaching a maximum length of 2.6 meters (8.5 feet). While they are known to display territorial behavior towards other fish, they are notoriously friendly towards scuba divers. They often follow divers around for the duration of their dive, and are even known to nudge divers and nibble on hanging equipment.
Their mouths are full of dense rows of backwards-facing needlelike teeth, allowing them to grab ahold of prey and swallow it whole.
They can change their skin color to enhance their camouflage, as well as to express their mood.
We saw this friendly grouper while diving in Ponta do Ouro, Mozambique