Similans Dive Sites – Koh Tachai

Similans Dive Sites – Koh Tachai

Koh Tachai is another awesome dive site here in Thailand and is often visited on the way to Richelieu Rock on your Similans liveaboard trip. It is the northern most island in the Similans National Park and offers 2 fantastic dive sites, the most popular one being Koh Tachai Pinnacle. This is a submerged plateau of boulders and hard corals with lots of channels and swim-throughs. The site attracts manta rays and whale sharks as well as large schools of barracuda, tuna and jacks. There is a also a group of resident batfish. It is a great place to dive in the early morning or at sunset when the blue-fin, golden and giant trevallies are out hunting.

Availability

End of October – Early May
As part of a 2, 3, 4 or 5 day Similan Islands liveaboard trip. Certified divers only.

Visibility

10 to 30 metres

Currents

Often moderate to very strong

Depth

30+ metres

Marine Life

Scuba Diving at Koh Tachai
Mantas are frequent visitors here

Manta rays, whale sharks, chevron barracuda, Great barracuda, trevallies, batfish, jacks, snappers, brown-marbled groupers, clown anemonefish, scorpionfish, lionfish, pipefish, cornetfish, trumpetfish, sea moths, boxfish, angelfish, triggerfish, moray eels, nudibranchs, octopus. Occasionally turtles. leopard sharks guitar sharks.

This is another of our favourite dive sites in Thailand and it is always an amazing experience. Manta rays are often encountered here and we’ve seen as many whale sharks, if not more on this site as we have at Richelieu Rock.

Koh Tachai is considered to be one of the top dive sites in Thailand and is located twenty-five kilometers north of Koh Bon. The main dive site is known as ‘The Pinnacle’ and then there is a second pinnacle to the north that is usually difficult to get to due to strong current.

Koh Tachai Pinnacle is a fairly advanced dive site and there is often current but it is an amazing dive. You will descend down onto the site on one of the two mooring lines making it easier to descend when there’s current. The shallowest area is at around 12 metres and the central feature of the dive site is a huge granite boulder. More large boulders are littered all around this centre rock creating canyons, overhangs and coral plateaus covered in fish life. There are several flat areas that have varying depths, stepping down to 30m and deeper. Brown-marbled groupers and Oriental and Andaman Sweetlips hang out in the shadows under the boulders. The hard coral areas are home to many types of moray eels, anemones and anemone fish and an assortment of colourful butterfly fish and angelfish.

You’ll see lots of soft corals, sea fans and big schools of snappers swimming around, while huge schools of many types of fusiliers feed in the open water. The schools of jacks and barracuda circle around the site endlessly while several types of trevallies hunt and dart around, coming very close to divers, making for an unforgettable experience.

All over the dive site there is so much to see but have a look out on the sandy patches surrounding the pinnacle too as there are often leopard sharks resting there. Sometimes the current is very strong but that brings in lots of fish – you just need to hang on to the edge of one of the large rocks and watch the show. The main pinnacle is too deep and the currents too strong for reasonable and safe night diving but its a great spot for a sunset dive while all the larger fish are out hunting.

Koh Tachai also boasts a beautiful sandy beach on its northeastern shore which is well worth the visit if you get the chance on your liveaboard trip. There is a tiny ranger station there now to keep the area clean. Off the beach there is a reef that stretches for the length of the island and is also another very nice site where you can sometimes see reef sharks and manta rays.