Diving Similan Islands

Deep Six

Located just to the north of Koh Pabu, Similan Island number 7, Deep Six is, as the name suggests, one of the deeper sites you're likely to encounter when diving in the Similans. Huge granite boulders form a rocky V-shaped ridge that starts just 5m below the surface and plunges down beyond 40m. The 'V' points north into deep water and the sides of the 'V' form the reef slopes of the island.

Currents can be strong at Deep Six so this is a dive site for intermediate to advanced divers. The best section of the site is located to the north and close to the rock jutting out of the water and marking the dive site. The best plan is to go deep out to the north to start with and make your way back up along the ridges.

Descending down the buoy line here, there are several spectacular swim-throughs, at about 10m or so. Corals include small table, wart finger and leather corals. It's easy to spot boxfish, lyretail grouper and the gorgeous powderblue surgeonfish. Butterflyfish, bannerfish and Java rabbitfish are also common schooling residents.

The boulder ridges house gorgonian sea fans, table corals and featherstars, with sea cucumbers and blue sea stars also hanging on. Moray eels are numerous and you can see emperor angelfish, parrotfish, and triggerfish.

Fusiliers are many in number and this of course attracts the larger hunting fish such as bluefin trevally and giant trevally. You may even see dogtooth tuna approaching causing the fusiliers to scramble for cover. If you're looking for pelagic action then you may be lucky enough to see a passing whale sharks or a manta ray. Barracuda are also commonly seen cruising out in the blue.

As you dive deeper then blue-spotted sting rays are in abundance, along with circling white tip reef sharks and leopard sharks resting on the bottom; all common sightings when diving the Similan Islands.

Deep Six was one of the few Similan dive sites that suffered damaged during the devastating tsunami on 26 December 2004. Consequently you can see snapped and overturned table corals, broken sea fans and dead gorgonian fan exoskeletons. Smaller pieces of coral and rock lain strewn around amongst the barren slopes where there once used to be flourishing coral reef.

Deep Six Reef Basics: Boulder ridges
Depth: 5 - >40m
Visibility: 215 - 30m
Currents: Can be strong
Surface conditions: Can be rough
Water temperature: 26 - 29°C
Experience level: Intermediate
Number of dive sites: 1
Diving season: October to May
Distance: ~90 km northwest of Phuket, 65 km west of Khao Lak
Access: Liveaboards and daytrips

• Koh Similan tourist information

View a map of:
• Similan and Surin Islands  -  Thailand

Scuba diving vacation enquiries

Back to diving in Similan index