Our boat captain expertly finds the edge of the wall, leading us to conclude that he has definitely done this before (yes, well, the GPS helps a bit too).

As we hang on the safety line, we look below us and see right through the blue water to the coral-covered bottom at 60 feet. Through this dense cover a sand trail wends its way, leading to the edge of the drop-off. The coral is clean and healthy, combining many different species in a carpet of living organisms.

We swim to the east enjoying the colourful display of boulder, star, brain, and finger coral until we come to the first of the real canyons. A narrow cut descends through the wall from 60 to 120 feet. The sides of the cut sprout deepwater sea fans, so peering out into the blue is like looking through complex wrought ironwork.

At the bottom of the cut, the wall descends further. Deeper it is more a steep slope than a wall.

You can cover as many canyons as your air consumption will allow before turning back and swimming along the top of the wall until you reach the anchor line. Hovering close to the reef we admire the tube worms embedded in the coral. Although colourful, they are almost lost in the background of reds, oranges, purple and greens of the hard corals.

Even with a good covering of coral, there is room for sponges to grow. Brown volcano sponges and vase sponge crop up, as do fiery patches of red algae. Fish are mainly small—blue chromis, damselfish, sergeant majors, hamlets, tangs and juvenile parrotfish. Black durgons are abundant and a couple of barracuda and a school of Atlantic spadefish join us for the last portion of the dive.

Back on the boat joining in the post-dive enthusiasm, we acknowledge that a dive on good coral is never boring.