Milln Reef is an outer Great Barrier Reef site in the Coral Sea, reached by boat from Cairns or Port Douglas. The six sites in our database span reef tops, walls, pinnacles, and drift dives, with depths ranging from shallow snorkel-friendly sections down to thirty-five metres. Sites suit beginners and intermediate divers, and all access is by boat. Recorded species include whale sharks, whitetip and blacktip reef sharks, green sea turtles, Napoleon wrasse, giant moray, and bluespotted fantail rays. Visibility is consistently noted above fifteen metres across the sites. The dry season tends to bring the clearest water, though diving is viable throughout the year.
Monthly water temperature across Milln Reef's sites, from satellite sea-surface data corrected for depth. The band shows the site-to-site spread.
Water temperature stays warm year-round, peaking in late summer and early autumn and dropping slightly through mid-winter. The dry season from mid-autumn to mid-spring generally delivers the most reliable visibility on the outer reef.
Water temperature around Milln Reef ranges from about 25°C in June to 29°C in March, based on satellite sea-temperature data for its dive sites.
In the warm season (about 29°C) a rash guard or 3mm shorty is comfortable in Milln Reef; in the coldest months (about 25°C) step up to a 3mm full suit.
Fin maps 6 sites in Milln Reef (6 scuba diving sites and 2 snorkelling spots, with some suited to both).
