Gretas Reef is a rocky reef near the Gold Coast Seaway entrance, described by Gold Coast Dive Adventures as several long boulders that run parallel to each other with a number of small to large colourful bommies. The boulders sit in 16-20 m on a sand bottom at about 20 m, and the parallel layout makes navigation easy: divers can follow one line of boulders out and another back, detouring to the bommies along the way. The operator rates it suitable for open water divers.

The bommies are covered in sponges, soft corals and feather stars, and they provide shelter for a good range of reef life. Nudibranchs are a highlight for macro enthusiasts, and moray eels, lionfish and wobbegongs occupy the gaps between boulders. On the sand, divers find flathead and sole camouflaged against the bottom.

Larger visitors are part of the appeal: Gold Coast Dive Adventures notes that dolphins and sharks are seen feeding on the reef, attracted by the schools of baitfish that gather over the rocks. Visibility is typically 8-20 m and is at its best after southerly winds and in the cooler months. Gretas is close to the Scottish Prince and Migaloo Reef, so it is easy to combine with either on a double dive from Runaway Bay.

For new divers who have done the Seaway and the Scottish Prince, it is a good step up to an offshore reef dive at a comfortable depth, and for photographers the bommies offer colourful subjects. Winter water rarely drops below 19°C.

Boat access only. Gold Coast Dive Adventures departs Runaway Bay Marina (Bayview Street, Runaway Bay – parking, cafes, toilets), runs south down the Broadwater and out through the Gold Coast Seaway; the reefs off the Seaway and The Spit are 10-20 minutes from the marina. Private boats launch at the Seaway/Broadwater ramps (e.g.

Doug Jennings Park area, Southport, Runaway Bay) and must cross the Seaway entrance, which can be rough on an outgoing tide against an easterly swell. Gretas Reef lies close to the Seaway entrance, beyond Migaloo Reef.

Offshore Gold Coast reefs sit in open water and are limited by swell and wind: easterly or south-easterly swell over about 1.5 m and south-east trade winds over 15-20 knots make the sites rough and stir up the bottom, while summer north-easterly sea breezes build through the afternoon. Visibility is typically 8-20 m, best after several days of southerly or westerly winds and in winter, and poor after heavy rain when the Nerang River and Broadwater outflow spreads along the coast. The Seaway crossing is safest on the incoming tide.

Descend to the boulders at 16-18 m, follow one boulder line along its length and return along the neighbouring one, detouring to the bommies. Keep an eye on the sand for flathead and sole.

Gold Coast Dive Adventures (Runaway Bay) – regular local reef dives.