Coral hind (Cephalopholis miniata) on a coral reef, with a small cleaner wrasse (blue, lower left). The coral hind is a type of grouper. It is a predator, feeding mainly on small shoaling fish. It can reach a length of around 40 centimetres. Cleaner fish have a symbiotic (mutually beneficial) relationship with their host fish: the fish remove harmful parasites from the fish's body and in return are allowed to feed unharmed. Photographed off the Solomon Islands.