Umm El Aruk

The dive

Umm Aruk, also written Umm Arouk and Um Arouk, is one of the St John's reefs in Foul Bay, the bay that opens south of the Ras Banas peninsula near Hamata. The pin sits essentially on the Tropic of Cancer, which is where the St John's group lies, roughly 210 km south-southeast of Marsa Alam and about fourteen hours of steaming away. This entry carries no destination in the catalogue and that is honest: there is no town, no shore and no day-boat access to this part of the coast. Southern liveaboards working out of Port Ghalib, Marsa Alam and Hamata are the only way to dive it, and the reef is worked from the boat and by zodiac.

On the surface it looks like very little, but the reef covers about 200 by 250 m. The name translates roughly as "mother of coral towers", and the towers are the reason to be there. On the eastern side, behind two boulders that come all the way up to the surface, stands a field of about two dozen coral pillars 6 to 9 m tall and 2 to 4 m across, rising off a sandy floor. In the south a craggy reef edge falls away as a plateau worked between roughly 5 and 14 m, and the western side has more boulders and mushroom-shaped ergs with garden eels on the sand between them. One operator publishes 10 to 40 m for the site, but that figure is the seabed continuing to fall away past the reef; the structure that makes the dive sits in the top 20 m, and swimming through the pillar field is what the dive actually consists of.

Operators working the reef report juvenile whitetip reef sharks in the sloping lagoon-like grooves, eagle rays over the western sand, and bannerfish and butterflyfish in numbers along the north side, plus large shoals of sweetlips. OBIS holds 60 taxa within about 11.5 km of this pin, a radius wide enough that it covers the neighbouring St John's reefs as well as this one; giant moray, humphead wrasse, coral hind, black-and-white snapper and moontail bullseye are the most frequently logged, alongside spinner and pantropical spotted dolphins and occasional oceanic whitetip shark. The pillar field and the eastern side are also used as a night dive, where Spanish dancers are the thing people go looking for.

The site is published as easy and open to all levels, with Open Water as the stated minimum, and on most days that is fair. The caveat is water movement: the liveaboard with the most detailed description of this reef says the current arrives from all directions and is not predictable, though the swirl between the pillars can be used rather than fought. Treat the briefing direction as a starting assumption rather than a fact.

• A field of roughly two dozen coral towers, 6 to 9 m tall and 2 to 4 m across, on the eastern side
• Two boulders on the east that come all the way to the surface
• Southern plateau worked between about 5 and 14 m
• Mushroom-shaped ergs and boulders on the west, with garden eels on the sand
• Juvenile whitetip reef sharks in the sloping lagoon-like grooves
• Night dive among the pillars, with Spanish dancers as the target

Conditions

An isolated reef in open water in Foul Bay, small enough that a boat moors at it and works the whole thing over a couple of dives. It is sheltered enough to be used as an overnight mooring and for night dives. Navigation is by structure rather than by a single reef wall, since the eastern side is a field of pillars, and current strength and direction is the variable that changes the dive from one day to the next.

On current: Sources split on how much current to expect. Operators selling the site describe it as easy and suitable for all levels, and the reef is sheltered enough to moor at overnight. The liveaboard with the most detailed description of the reef is more specific and less reassuring: the current here comes from all directions and is unpredictable, and the useful skill is reading the swirl between the coral pillars rather than following a briefed direction. The depth numbers also diverge. The sandy floor the towers stand on and the southern abrasion edge both sit at about 20 m, and one operator publishes 10-40 m for the site because the seabed keeps dropping beyond the reef. The page uses 20 m, because that is where the diving is.

Dives & underwater footage