The Colours is the Eastern Suburbs' signature deep reef and is named honestly: the walls are plastered in sponges, sea squirts, ascidians and gorgonians in reds, yellows, oranges and purples that are as vivid as anywhere on the NSW coast. The reef is a plateau roughly 150 m long with its top at about 22 m. From the northern end the edge runs south-east, then south, then swings back south-west and west, and along most of that length it drops to the sand in one or two dramatic walls.

At the northern end the wall goes to 28 m and the bottom continues down gradually past 30 m to 33–35 m further out; the southern end is gentler, breaking into gullies and boulders with a less distinct face. Intermediate ledges at about 26 m give a natural profile for a multi-level dive. A curiosity at the northern end is a series of large circular holes about a metre deep in the reef floor at 28 m.

The Inner and Outer names used by charter operators refer to the shallower western side and the deeper outer wall. Fish life varies from sparse to spectacular between dives: at its best the bottom disappears under thousands of silver sweep and one-spot pullers, with big schools of seapike, yellowtail and mado above the wall, plus black reef and mosaic leatherjackets and small bream working the growth. Because of the depth this is a short dive – 17 to 22 minutes on air before decompression – so it is typically run as the first of two dives with a shallow second at Bondi or The Gap.

It suits advanced divers comfortable at 30 m with good buoyancy on a wall; it is not a site for newly certified divers or anyone unused to Sydney's currents. The value is the combination of colour, scenery and the chance of a fish-storm within half an hour of the harbour.

Boat only. From Sydney Harbour, turn right (south) out of the Heads and head out at roughly 45 degrees for about 1.5 km until you are off the old Macquarie Lighthouse (the southern of the two lights); it is about 20–30 minutes from Rose Bay or Rushcutters Bay. Find the reef on the sounder – the top comes up to 22 m from 30 m sand – and anchor on the reef top in a westerly or on the sand edge in an easterly.

Charter boats from Rose Bay, Bondi and Coogee all run here; from Botany Bay it is about 12 km north.

A fully exposed offshore reef. Anything over about 1.5–2 m of swell from the south or east makes anchoring and the surface interval uncomfortable and reduces visibility; north-easterly sea breezes above 15 knots chop it up in the afternoon, so charters dive it first thing in the morning. Current along the reef is common and can be strong enough to require a live-boat drift and SMB; check the anchor line before committing.

Depth rather than weather is the limiting factor – the reef top is 22 m so the no-decompression window is short. Visibility is often excellent in winter and autumn (20 m+) and drops after big east-coast lows and heavy rain from the harbour plume.

Descend the anchor to the reef top at 22 m, drop over the northern wall to 28–30 m and follow the wall face south-east then south, keeping the wall on your left. Look at the metre-deep circular holes in the reef floor at the northern end. Turn after 8–10 minutes or at the planned NDL, ascend to the 26 m ledge then the 22 m reef top for the return, and do a long safety stop on the anchor line in blue water.

Nitrox 32 is strongly recommended; on air plan 17–20 minutes at depth.

Nitrox 32 ideal (MOD 33 m); decompression divers can extend along the 33–35 m outer slope.

Dive Centre Bondi (most weekends), Pro Dive Coogee, Frog Dive and Southern Cross Divers run this as a first deep dive of a double-dive day; Abyss Scuba Diving and Sydney Dive Academy visit less often from Botany Bay.