The picture was created in Goat Island marine reserve near Leigh, New Zealand. It’s a great place to photograph snapper there, the reserve has a resident population of these fish, from babies to old patriarchs. Snapper are fished heavily along the NZ coast, so it’s quite difficult to approach them underwater. Not so in the reserve. The reserve is a great photo studio, especially in winter. The kelp covered reefs provide a great scenery and the fish are not disturbed by Swimmers or snorkelers.
My personal tip: Go there in the end of winter (August) during a week day. There are usually only a few people on the beach and almost certainly nobody in the water. If you meet a diver, it’s usually another photographer.