This cluster of submerged boulders is located on the north of Similan Island 7 (Koh Pa-Yu). Deep Six is an extension of the main island that continues underwater, with a maximum depth of 35 to 40 meters. There are many outcrops throughout the area, along with scattered rocks with soft corals and sea fans on the outer parts. As the big boulder in the center, a pile of smaller rocks form swim-throughs, at depth of between 12 to 22 meters. In addition, there are sheer walls covered with dense soft corals. Shallow patch corals and rocks surround the island at a depth of 10 to 15 meters.
Moderate, sometimes strong current, particularly at the pointed end of the reef, where the current can often make you drift off the boulders. The current flows in a southeast to northwest direction and vice versa.
You may see whitetip reef sharks off the boulders, and Kuhl’s stingrays are common on the sandy areas. You’ll find black and white snapper, giant trevallies and tuna swimming among boulders. As well as schools of neon fusiliers, bluefin trevallies and yellow snapper.
When passing the swim-throughs, you may encounter big snappers, oriental sweetlips or harlequin sweetlips, and if you’re lucky, you’ll spot ghost pipefish and frogfish camouflaged among the pinnacles. The lush corals are home to various small marine critters such as red fire gobies, blennies and nudibranchs.