Small Crack

The outer side of the Sha'ab Mahmoud barrier is a coral wall that falls to a sandy floor around 20 metres, hung with gorgonians, alcyonarians and large table corals. A zodiac drops the group on this wall and the drift runs south with the ebb towards the crack, which is the preferred window for the dive. The wall gives way to the passage, 5 to 8 metres deep, and the current carries divers through it and out into the lagoon, where the boat waits at its mooring.

Turtles are often seen along the outer wall, with leopard sharks and whitetip reef sharks. Summer brings schools of barracuda and jackfish.

Small Crack is a boat dive from start to finish. Liveaboards moor in the lagoon behind the reef, so the zodiac ride round the barrier is how a diver reaches the wall, and the crack is the way home. The passage can also be part of a Thistlegorm overnight trip.

A large coral formation splits the gap into two channels, and the dive threads through them from the open strait into the lagoon behind. Small Crack is the southern of the two passages that cut through this reef; the other, Big Crack, lies about seven kilometres to the north-west.

The lagoon is a sheltered overnight anchorage for liveaboards, and operators pitch the passage as a night dive for its resident flashlight fish, weather permitting.

The current through the crack can become extremely strong, and the zodiac cover and the guide's tide window are the safety net. Fire coral is abundant near the mouth of the channel, so settle trim and buoyancy before the drift carries you in, and stay with the group through the passage.