

The 4th-5th Reefs sit at 15 to 17 metres off the New South Wales coast and offer a solid mix of temperate reef species that reward patient, observant divers. Visibility typically runs 5 to 10 metres, giving you enough range to scan the bottom for resting angel sharks and wobbegong blending into the substrate. Keep a closer eye on rocky ledges and crevices for Port Jackson sharks and the vivid eastern blue devil. Weedy sea dragons and cuttlefish appear regularly, while schools of yellowtail, luderick, and old wife move through mid-water. There is no significant current, so you can take your time. Boat traffic is the main hazard, so a surface marker buoy is essential.
-34.07050, 151.15800
The site dives best from October through May when water temperatures are more comfortable and marine life activity is at its peak. Whether you enter from the shore or a boat, deploy your SMB before ascending as vessel traffic in the area can be busy.
Shore access is from Oak Park, at the end of Jibbon Street, Cronulla. Entry can be made from either side of the ocean pool. The site can also be accessed by boat.
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The area can be crowded with other boats and surfers.
Depth
15-17m
Visibility
5-10m
Skill Level
Intermediate
Entry
Shore & Boat
Water Temp
14-21°C
Current
None
Best Time
Jan, Feb, Mar, Apr, May, Oct, Nov, Dec
4th-5th Reefs in Sydney, New South Wales is home to iconic Australian species including weedy sea dragons, blue groper, and three shark species: wobbegong, Port Jackson sharks, and angel sharks. Divers also regularly encounter cuttlefish, eastern blue devils, and old wife fish across the reef system. The site's moderate depths of 15 to 17 metres make it accessible for observing this diverse marine life.
The 4th-5th Reefs dive site ranges from 15 to 17 metres deep, making it a comfortable depth for intermediate divers. This shallow to moderate depth profile allows for extended bottom times and reduces nitrogen loading. The relatively shallow depths also support excellent reef biodiversity in Sydney's temperate waters.
A boat is not required to dive 4th-5th Reefs as the site offers both shore and boat entry options. This flexibility makes it accessible for independent divers with their own transport as well as those joining organised boat charters. Shore access provides convenient diving opportunities near Sydney without the need for vessel arrangements.
Open Water certification is required to dive 4th-5th Reefs in Sydney. The site's intermediate skill level designation and depths of 15 to 17 metres make it suitable for divers who have completed basic Open Water training. Divers should be comfortable with navigation and boat traffic awareness at this location.
4th-5th Reefs offers optimal diving conditions from October through May, covering eight months of the year. This extended season corresponds with warmer water temperatures ranging from 14 to 21 degrees Celsius and generally calmer sea conditions. The site remains diveable year-round, but these months provide the most comfortable conditions for intermediate divers.
Night diving is permitted at 4th-5th Reefs, offering opportunities to observe nocturnal marine behaviour in Sydney's waters. The site's moderate depths of 15 to 17 metres and lack of strong currents make it suitable for night dives with proper training. Divers should be particularly aware of boat traffic hazards when conducting night operations at this location.
Boat traffic is the primary hazard at 4th-5th Reefs, requiring divers to deploy surface marker buoys and maintain awareness during ascents and surface intervals. The site's proximity to Sydney means recreational and commercial vessels may pass through the area. Divers should follow standard boat traffic protocols including proper flag deployment and listening for engine noise before surfacing.
4th-5th Reefs in Sydney is best suited for divers with some experience. You should be comfortable with your buoyancy and have logged at least 10 to 20 dives.
A 7mm wetsuit or semi-dry is recommended for diving at 4th-5th Reefs in Sydney. Water temperatures range from 14°C to 21°C.