Exploring Koh Tao’s Underwater Marvels & Diver Training

IDC rescue exercises in Koh Tao
IDC rescue exercises in Koh Tao

AL HORNSBY heads for the island of Koh Tao in Thailand and is pleasantly surprised by the rich diversity of underwater experiences – as well as the professional diver training on offer

For a number of reasons, the small island of Koh Tao off Thailand’s eastern coast is considered one of the most popular Thai resort destinations. Like many other islands in the country, it has a reputation for fun and partying – it’s one of the monthly ‘Full Moon Party’ islands, after all – but it has other attractions to offer, not least under water.

Chumphon Pinnacle, Koh Tao Thailand
Rich life on Chumphon Pinnacle

Its crowd, largely European and Asian, is more of a mix of young and somewhat older people than is seen on most of the other islands, because it includes many repeat travellers who first visited when they were of university age and who now come back with their families.

Also read: Deported diver returns – but faces pipefish charge

While there is no shortage of great bars, restaurants and late-night clubs, Koh Tao has a clean, laid-back atmosphere that chimes with the beauty of its natural, tropical-island environment.

And, while Koh Tao’s granite-boulder geology and steep mountainsides create an appealing landscape for hikers and climbers, the island’s biggest recreational draws are its scubadiving and snorkelling. Its name means Turtle Island and it is a nursery area for frequently seen greens and hawksbills. Its beaches and near-shore waters offer surprisingly vibrant and varied dive-sites. 

Top training

Despite Koh Tao’s small size – it covers only 21sq km, and much of that sparsely populated mountainsides – it has become one of the top dive-training locations in the world, with thousands of people each year enjoying PADI Discover Scuba experiences, gaining their Open Water Diver certifications, and moving on up through Advanced Open Water and other continuing-education levels.

To top it off, it has become one of diving’s top professional-level training centres, and claims to have more trained more divemasters and instructors each year than any other island.

When you visit Koh Tao for the first time, you might wonder how it managed to evolve in this way. Well, it helps that it does have some excellent, progressive dive-operators who make it seem natural and easy to expand one’s diver training while enjoying diving each day; affordable prices; and a pervasive, tranquil, tropical loveliness.

Its secret, however, is one that is often underplayed when discussing Koh Tao, and that is the extraordinary quality and diversity of its diving. 

Talked down

Black-coral diving in Koh Tao
Black-coral diving in Koh Tao

As someone fortunate enough to visit many diving destinations, my welcome to a new area usually begins with tales of how incredible the diving is, with all the life and marvels we’ll see – claims that are virtually always accurate and that I’m certainly happy to hear.

Koh Tao was different, however. The attitude was far more reserved and conservative, and I got the initial impression that the diving would be very nice but nothing to write home about.

If this was by design (and I don’t think it was), to lull me into modest expectations while knowing that I’d be blown away the moment I hit the water, I have to say that it worked. I can honestly say that never have I been so surprised by the richness and diversity of a new dive location as I was by Koh Tao. 

The environment was dramatic and chock-full of life, a marine-species-on-parade experience in unique settings. Here are just a few of the accessible dive-sites, by way of example:

Sail Rock

This site is in fact a two-hours boat-ride away, but regularly dived. Sail Rock lies in open water between Koh Tao and Koh Phangan and is an iceberg-shaped, life-covered pinnacle, with surrounding additional submerged peaks, that rises steeply from a 45m sand bottom.

While it is famed for its winding, well-lit chimney that extends from 18m to within 5m of the surface, for me Sail Rock’s special magic was its profuse collection of marine life, with massive schools of fish as well as large solitary species in generally very good visibility (the week I was in Koh Tao it ranged between 15 and 40m). 

In my two dives there I photographed several types of large grouper, as well as large schools of longfin spadefish; a huge swarm of yellowfin barracuda, followed a little later by a school of pickhandle barracuda. Soon afterwards I was enveloped by bluelined barracuda and there were also vast shoals of yellowtail scad, all milling around the gigantic spire.

What we didn’t see were any whale sharks, which we were told were regularly present – though Koh Tao saved that for just a couple of hours later.

South-west Pinnacle

The third dive of our day-trip to Sail Rock was at a marvellous place known as South-west Pinnacle (you guessed it, south-west of Koh Tao). A group of seven underwater peaks and ridges that extend from 30m to within 5m of the surface, this is a varied, impressive area, with large patches of anemones covering the rocky faces, most with resident pink anemonefish, and with many small groups of Java rabbitfish milling about.

Lovely and interesting as this all was, however, it was the 8m whale shark that really grabbed our attention. During our 45-minute dive, this huge shark made four or five quick passes – and what an incredible sight it was, especially in this unique setting.

Whale shark
Whale shark

Sattakut shipwreck

Not far off the western shore of Koh Tao, we dived a very interesting shipwreck, the Sattakut. This 48m US Navy LCI (landing craft, infantry) saw considerable action during World War Two throughout the Pacific theatre, and after the war became a part of the Thai Navy.

Sunk as a dive-site in 2011, the wreck rests with its stern at 30m, the bow at 26m and the bridge at 18m. Its two guns are still there, the most dramatic being its 76mm bow cannon.

Around the wreck we saw sting rays in the sand and giant grouper, sweetlips and several species of snapper congregating about the deck and superstructure. Penetrations were possible for those of us with the appropriate certifications.

Chumphon Pinnacle

Every destination has its favourite dive and for me, as enjoyable as my dives around Koh Tao had been, the finale now lives in my all-time favourite dive sites list.

This was a long, submerged pinnacle off the north-western tip of the island. Rising from a 40m sand/rubble bottom to within 14m of the surface, Chumphon is drama personified.

We dropped onto a huge panorama of mountainous ridges and spires extending outward in seemingly every direction, dizzyingly complex in the 35m vis and crystal-blue water. 

The surfaces of the rocks were decorated with large gorgonians, black coral bushes and sponges. Most spectacular, however, were the seeming hectares of slopes completely covered with huge emerald, gold and violet-coloured anemones. Massive schools of flashingly bright yellowband fusiliers swirled above them all, all making for a scene that was near-indescribable. 

As we moved about we found large brown-marbled grouper, coral cod and groups of giant sweetlips. At one spot on the sandy bottom, a large school of squid moved about, hunting over the sand.

Yellowband fusiliers and an African pompano
Yellowband fusiliers and an African pompano

And, as if not to allow the dive to end on a quiet note, during our safety stop a group of four young African pompano begin making rapid, flash-by passes at us, with one of them periodically extending its “streamer” threadfins in display, before instantly retracting them.

For many minutes I followed them through my viewfinder, repeatedly firing, trying to capture the millisecond of the display without being able to tell if I ever caught it or not. Later, on the boat and looking closely at my images one unusual photograph emerged of the four chromium-hued pompano with the biggest at the centre in full display.

My brief visit to Koh Tao had brought some special surprises. 


Sairee Cottage Resort, located along the water on Koh Tao’s most popular area Sairee Beach, is considered an island pioneer. Many long-time local pros have been associated with it at some time in their careers, whether receiving training, working or living there – in the old days for about the cost of a burger a night!

These days it remains a fixture of the Koh Tao dive scene, having developed into a modern resort but without losing any of its casual on-the-sand charm. 

The resort has a dive-centre, training pool and classrooms, wi-fi and the other amenities expected by modern travellers, along with several restaurants around the property and many more accessible within a short stroll. The accommodation includes beach and garden bungalows, poolside and garden rooms and a comfortable dormitory (included in the price of Go Pro training programmes).

The PADI 5* IDC combines fun-dive offerings with diving and snorkelling training programmes. A sizeable percentage of its open water-certified guests started out simply fun-diving, only to decide that by the end of a week’s stay they could earn their Advanced OWD credentials and more along the way.

Koh Tao, Sairee Cottage pool
The Sairee Cottage pool

Divers interested in going pro find the required PADI Dive Master and Instructor Development courses but also internship and mentoring programmes that help build real-world experience. The Go Pro PADI Instructor programme is led by Platinum Course Director Marcel van den Berg who, with his IDC Staff, conducts hands-on, close-attention programmes that receive high marks from their candidates.

Open Water Scuba Instructors can proceed to the Master Scuba Diver Trainer programme, which not only teaches the five instructor specialities required but also gives the OWSIs the opportunity to teach and certify the 25 divers needed for MSDT certification. This can be accomplished in about two weeks, though the full internship programme can be enjoyed for up to six weeks, giving candidates considerable training and teaching experience before they enter the dive industry.

Recreational divers interested in undergoing such professional training – or who simply want to stay and dive with the centre – can visit the Sairee Cottage Diving site.

Photos by Al Hornsby

Also on Divernet: Similan Islands: Diving The Sea Of A Million Stars, ‘I’d Been Wreck-Hunting When Our Dive-Boat Sank’, The Ship’s Bell


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1 month ago

Don’t bother unless you have zero skill, koh tao was an absolute dump with unskilled DMs and way too many divers on one spot.

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