Meet the site
Blue Lagoon on Hastings Reef is a Divers Den site on the southern side of the reef, and it is quite different from the similarly named lagoon on Thetford Reef. Divers Den describes a shallow shelf of coral with a deeper shelf below it and walls extending on either side, so the dive is a pleasant combination of terraces and walls rather than a sandy lagoon. The shallow shelf is bright and colourful, well suited to snorkellers and new divers, while the lower shelf and walls give certified divers depth and structure. A feature of the site is elephant-ear coral, the broad, folded colonies of Mycedium, with small shrimps hiding in the folds, surrounded by table corals. Hastings Reef as a whole supports butterflyfish, damselfish, clams, turtles and small reef sharks, according to Divers Den, and Cairns Dive Adventures adds large schools of humphead parrotfish, which move around the reef in the mornings. On the walls look for anemonefish, angelfish, coral trout and cod, and on the terraces for giant clams and sea stars. The dive is straightforward and suits all levels; less experienced divers can stay on the upper shelf and still see plenty. Blue Lagoon and Angel Bommie are close enough that guides sometimes combine them in one dive. Angel Bommie, a sandy staghorn bay with its own entry, adjoins it, and the two are close enough that guides sometimes combine them in one dive. Visibility is usually 12-20 m, and the upper shelf is at its most colourful on a sunny day around high tide.
What you might see
Elephant-ear coral with shrimps, table corals, butterflyfish, damselfish, giant clams, turtles, small reef sharks, humphead parrotfish, anemonefish, angelfish, coral trout
Location
Divers Den site on the southern side of Hastings Reef, about 50 km north-east of Cairns: a shallow coral shelf above a deeper shelf with walls extending either side.
Facilities nearby
Departs Reef Fleet Terminal / Marlin Marina, Cairns: toilets, cafes, paid parking; dive gear, tanks and lunch supplied on board
Before you make plans
Conditions, access and operator schedules can change. This is a location guide, not a dive plan. Ask a local operator about current conditions and suitability for your training and experience.
Sources & further reading
diversden.com.aucairnsdiveadventures.com.auRecord updated 26 Sept 2026. Source claims are being reviewed.