Indicators is an offshore reef area listed by marinelife.org.au as lying well out from Canal Rocks in 20-30 m, with spectacular walls and caves rich in marine life and fish. The name is shared with a surf break, a reminder that shallow reefs along this coast break in swell and that any boat approach should be made in calm conditions.

Walls and caves at 20-30 m on the open Indian Ocean coast suggest clear water, abundant fish such as western blue groper, dhufish and buffalo bream, and good sponge growth in the shaded areas. With few divers visiting, the reef is likely to be in good condition.

Because only a brief description is published and the position is not given, the site is a matter of local knowledge. It suits Advanced divers with their own boat who are comfortable at 20-30 m in open water and can plan around swell and current. Nitrox helps extend bottom time.

For divers without a boat, the Honeycombs and the sheltered north side of Canal Rocks offer shallower alternatives in calm weather.

The Capes coast between Cape Naturaliste and Cape Leeuwin faces the Indian Ocean and is famous for its surf, which is exactly what makes diving here so condition-dependent. Long-period south-westerly groundswell can arrive on calm, sunny days, and the regional ocean-safety guide advises observing a site in different conditions before diving it, never diving alone and flying a flag near boat ramps.

Launch at the Canal Rocks boat ramp on a calm day and run offshore to the reef; positions are local knowledge. Only suitable for capable boats in low swell. Boat ramps along Geographe Bay include Bunbury (Casuarina), Busselton, Port Geographe, Quindalup and Dunsborough; on the Capes coast the Canal Rocks, Gracetown and Hamelin Bay ramps are small and swell-exposed.

Check the forecast, carry a marine radio and log a trip plan with the local Marine Rescue group.

Offshore on the Indian Ocean coast; needs low swell and light easterly winds, usually summer and autumn mornings. Surf breaks on shallow reefs nearby. General pattern on the Capes and Leeuwin coast: summer mornings often have light easterly (offshore) winds before a south-westerly sea breeze, and long-period south-westerly groundswell can arrive on otherwise calm days; winter fronts bring big swell and north-westerly winds.

Check the Bureau of Meteorology swell forecast, not just the wind.

Descend the anchor line to the wall top, follow the walls and caves at 20-30 m within no-deco limits, and ascend on a DSMB. Agree a turn pressure before descending (half gas, or a third where current is likely), carry a DSMB, and make a 3-minute safety stop at 5 m.

Nitrox recommended.

No operator; private boats only. Nearest dive services: Swan Dive (Busselton/Port Geographe) for fills, hire, nitrox and charters; no dive shop in Margaret River or Augusta.