Dack Reef is the deep site of the Batemans Bay area. Spirit Divers described it as a deep dive and a nice site to complete a Deep Diver course or technical training, with a maximum depth of 40 m or more. The Marine Life Network lists it at 40 m for experienced divers and notes that it sits inside a Batemans Bay Marine Park sanctuary zone, with large underwater rock formations packed with sea fans and soft corals and good fish life.

At this depth the reef is below the kelp line and dominated by filter-feeding animals: gorgonian sea fans, soft corals, sponges, sea whips and ascidians. Fish include schools of yellowtail and sweep, red morwong, nannygai, bastard trumpeter and larger pelagic visitors. The sanctuary zone status means fishing is prohibited, which helps preserve fish numbers.

This is not a recreational dive for Open Water divers. On air, the no-decompression time at 40 m is very short and narcosis is significant, so it suits Deep-certified divers with experience or technical divers using appropriate gases. No detailed layout or GPS has been published, and the site is best done with a local operator who knows the reef and can provide appropriate support. Divers wanting to experience the deeper reefs of Batemans Bay without technical training could consider Burrewarra Point or The Maze at around 30 m, which are better documented and within recreational limits for Advanced divers.

Boat access only, with a local operator. Launch at the Hanging Rock ramp in Batemans Bay; the reef lies offshore within the Batemans Marine Park and no public GPS has been published. It is used for deep and technical training, so trips are organised with the operator; the run is probably 15–20 minutes from Hanging Rock depending on sea state.

Offshore and deep: surface conditions matter more than surge. Anchoring and recovering divers from 40 m requires light winds and small seas, generally swell under 1.5 m and winds under 15 knots. Current is more likely than inshore; divers must be able to ascend on the line or with a reel and SMB.

Visibility is usually better than inside the bay but can be reduced by runoff after heavy rain.

Descend the line directly to the reef, stay close to the anchor, and plan a short bottom time (about 8–12 minutes on air, longer on trimix with planned decompression). Ascend on the line with the planned stops.

Beyond recreational air limits for much of the reef; trimix (e.g. 21/35) or at least EAN/air with strict limits recommended. Plan decompression and carry redundant gas.

Spirit Divers used Dack Reef for PADI Deep Diver courses and technical training (40 m+, daytime only). The Marine Life Network lists it for experienced divers. Check current availability with Beneath the Bay.