Similan Islands Diving
Running from Island No. 3 and extending all the way to Boulder City, Sharkfin Reef is a long submerged rocky ridge. At low tide the ridge breaks the surface of the water to resemble a shark fin.
The site provides dramatic and contrasting scenery to those dive sites found on the eastern sides of the Similan Islands. The reef is made up of a series of massive granite boulders covered in gorgonian seafans and a variety of hard corals. It is like 2 different dive sites and can be dived more than once.
On the north-eastern side is a sloping reef of stacked boulders covered in hard corals and on the south west the boulders create a more prominent drop-off into deeper water resembling an underwater canyon. A large swim-through makes a natural passage way from one side to the other but be careful as you go so that you don't damage the delicate hard coral growth.
The reef has some prolific and diverse marine life with large cube boxfish, clown triggerfish, half-moon triggerfish, schools of batfish, palette surgeonfish, blue-faced angelfish and bannerfish. Look out for smaller marine life in among the rubble on the sand between the coral patches. Leaf fish are seen here as are blue ribbon eels. Nudibranchs are numerous too.
The deeper side is a good place to spot passing sharks and larger rays. Also look out for Napoleon wrasse, bumphead parrotfish and leopard sharks.
This is an impressive site for diving in the Similan Islands and is often visited as one of the last dives of a liveaboard trip.
Sharkfin Reef Reef Basics: Fallen boulders
Depth: 5 - 40m
Visibility: 20 - 40m
Currents: Can be strong
Surface conditions: Can be rough
Water temperature: 26 - 29°C
Experience level: Intermediate - advanced
Number of dive sites: 2
Diving season: November to April
Distance: ~90 km northwest of Phuket, 65 km west of Khao Lak
Access: Liveaboards and daytrips
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