Deep Six

Giant-Moray-Eel-Gymnothorax-javanicus-at-Deep-Sic-Koh-Similan-Thailand-Henry-and-TersiaGiant Moray Eel (Gymnothorax javanicus)
Photo by Henry and Tersia
Deep Six is one of the more exciting dive sites at The Similan Islands in Thailand. It got its name from being deep (obviously) and at Island 6, which was later renamed Island 7. The dive site is not for beginners, and can even be challenging for intermediate-level scuba divers. However, those who are able to dive here are sure to be impressed with the topography, visibility and wonderfully diverse marine life.

  • It's deep
  • Reef Sharks
  • Excellent visibility
  • Varying currents

This great diving site is made up of massive granite boulders which appear to have fallen down from the northern tip of Island 7. If viewed from above the sea and having the ability to remove the water, one would see an arrow head or large V of rocks, with its tip facing north. Either side of this V there are plenty of smaller boulders scattered around. The topography makes for plenty of swimthroughs varying in size and difficulty. The claimed maximum depth here varies, but most divers will reach their personal limit or run out of things to see before finding the true bottom. In addition to the lack of life down deep, air-sapping currents are going to reduce any regular diver's ability to go more than 50 metres on one tank. To be honest, with so much life and places to explore, there is no need to descend below 35 or 40 metres. Divers need to follow and obey their Divemaster at Deep Six, as he or she should be aware of how to get the best of every dive here. Currents need to be checked and managed, so staying near the Divemaster and rocks is advised. The mooring line is a little west of centre and will help divers to get down as deep as they plan to nice and early. From then on, they can slowly ascend while exploring and enjoying the multitude of swimthroughs, caverns, nooks and crannies. At the end of the dive, it is usual to swim out north into open water in order to be picked up by the boat. This is because the rocks in shallow water and the waves they cause make getting to close difficult and hazardous.

Frogfish-Antennariidae-at-Deep-Six-Koh-Similan-Thailand-Henry-and-TersiaFrogfish (Antennariidae) Photo by Henry and TersiaThere is plenty to see here at Deep Six, but for some reason, there are very few sightings of either Manta Rays (Manta alfredi) or Whale Sharks (Rhincodon typus). They have been seen, but generally pass by on other Similan dive sites during the diving season. However, there is still plenty of life all the way down this exciting stack of underwater boulders. Starting with other sharks and rays, it is not uncommon to see Whitetip Reef Sharks (Triaenodon obesus) or Blue-Spotted Stingrays (Neotrygon Kuhlii) either resting or swimming. Both species usually hang around until divers approach too near, then they swim away slowly. Medium-sized reef and schooling pelagic bony fish are all over the place at different depths here at Deep Six. Divers can expect to come across the likes of Rainbow Runners (Elagatis bipinnulata), Sweetlips (Plectorhinchus), Fusiliers (Caesionidae), Barracuda (Sphyraena), and Trevally (Carangidae) to name just a few. The Sweetlips are among fish who like to hide in the caverns and sheltered areas, and there are lots more species to see in there as well. Examples of smaller fish and invertebrates sheltering from danger are Frogfish (Antennariidae), Pipefish (Syngnathinae), Snapper (Lutjanus), Boxfish (Ostraciidae), Red Fire Gobies (Nemateleotris magnifica), lobsters and shrimps.

Unfortunately, the 2004 Asian tsunami had quite a severe impact on the hard corals at Deep Six. There is some natural debris which has never been removed and will never be eaten. Although the reef life here is recovering, divers will still be able to see some damage that was caused. However, with all the fish to look at and dive profiles and currents to think about, they should soon return their focus on the best diving in the area. Diving at the Similan Islands is an experience most people will never forget, and Deep Six is among the most exciting sites here. Access to Deep Six must be by either liveaboard boat or daytrip catamaran from Phuket or Khao Lak. We take bookings for every vessel - size and budget – which sails out to The Similan Islands Click below to see which package or tour best fits your needs, budget and plans.


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