Warm water year-round, whale sharks, coral reefs, and dozens of dive sites in the Gulf of Thailand
Koh Samui is located in the Gulf of Thailand — one of the best diving destinations in Southeast Asia. Thanks to its geographical location, you can dive here year-round, although conditions vary depending on the season.
The water in the Gulf of Thailand is warm year-round. The average temperature is 28-30°C, allowing comfortable diving in a thin wetsuit (3mm) or even without one. In winter months (December—February) the temperature may drop to 26-27°C at depth, but this is still very comfortable. No 'cold shock' — just the pleasure of warm tropical water.
Underwater visibility depends significantly on the season and specific dive site. In the best season (March—September) visibility at Sail Rock and pinnacles reaches 20-30 meters — you'll see everything in crystal clear water. During rainy season (October—December) visibility may drop to 5-10 meters due to plankton, but this is exactly what attracts whale sharks. We always choose the best dive sites depending on current conditions.
March—September is the peak diving season on Koh Samui. Calm sea, excellent visibility (15-30m), minimal rainfall. This is the best time for trips to Sail Rock, Chumphon Pinnacle, and other remote sites. October—December is rainy season with higher waves, but this is when whale sharks appear most often. January—February is a transitional period, with good conditions returning toward late February.
The Gulf of Thailand boasts incredible biodiversity. From tiny nudibranchs to giant whale sharks — every dive brings new discoveries.
The whale shark is the largest fish in the world, reaching 12-18 meters in length. They appear regularly at Sail Rock and Chumphon Pinnacle, especially from March to September. These gentle giants feed on plankton and are completely safe for divers. Encountering a whale shark underwater is one of the most thrilling experiences in any diver's life.
The pinnacles of the Gulf of Thailand are a magnet for massive fish schools. Thousands of barracuda, trevally, and fusiliers swirl around underwater rocks, creating incredible 'tornadoes' of silvery bodies. At Sail Rock and Chumphon Pinnacle, schools are so dense they sometimes completely block out sunlight. Large batfish, groupers weighing up to 100 kg, jacks, and mackerel also live here.
The coral reefs around Samui and Koh Tao are home to hundreds of species of fish and invertebrates. Clownfish in anemones, vivid parrotfish, elegant angelfish, quirky pufferfish, graceful rays, predatory moray eels, cautious octopuses, colorful nudibranchs. Sea turtles are frequent visitors to the reefs, especially green and hawksbill turtles. Every dive is like visiting a giant underwater aquarium.
All Poseidon instructors hold current PADI and first aid certifications. We use only tested, regularly serviced equipment. A detailed briefing is conducted before every dive. We work with small groups (maximum 4 divers per instructor) to ensure individual attention for everyone. Oxygen and a first aid kit are always available on board.
Training and briefings in Russian — no language barrier. This is especially important when training beginners who need to clearly understand all safety instructions. Our team also speaks fluent English, so we work with guests from any country. All PADI training materials are available in Russian.
We have our own boat with an experienced captain who has known the Gulf of Thailand waters for over 20 years. This means flexible schedules, comfortable conditions, and the ability to visit dive sites at optimal times. We don't depend on large tourist boats and can adapt the route to current conditions and your preferences.
No! You don't need a certificate for your first dive. The Discover Scuba Diving program lets you try diving with an instructor without prior training. You'll complete a brief theoretical course and dive up to 12 meters under constant instructor supervision. If you enjoy it, you can take the full PADI Open Water Diver course and receive a certificate valid worldwide.
The best period is March to September. The sea is calm, visibility is at its peak (up to 30 meters), and the weather is sunny. However, diving is possible year-round. Even during rainy season (October—December) there are days with excellent conditions, and the chance of spotting a whale shark is higher then. We'll always advise which sites are best to visit on any given day.
Absolutely safe! Whale sharks are gentle giants that feed exclusively on plankton. They pose no threat to humans. Reef sharks (blacktip and whitetip) found at pinnacles are shy and avoid contact with divers. In all our years of operation — zero incidents. The key rules: don't touch, don't chase, maintain distance.
A dive trip typically includes: hotel transfer, boat trip to the dive site and back, full equipment set (BCD, regulator, wetsuit, mask, fins, weights), 2 dives, lunch and drinks on board, professional instructor/dive master. For courses, PADI training materials and certification are additionally included.
Before your first dive, you'll need to fill out a PADI medical questionnaire. Main contraindications: serious heart and lung conditions, epilepsy, pregnancy. If you have chronic conditions, a doctor's note will be required. Asthma, diabetes, and other conditions aren't always absolute contraindications — discuss this with our instructor. Minimum age: 10 for PADI Junior, 8 for Bubblemaker.
Of course! The Discover Scuba Diving program is designed specifically for those who have never dived. Our instructor will thoroughly explain all the rules, show you how to use the equipment, and stay by your side throughout the entire dive. Thousands of people try diving for the first time on Koh Samui every year and fall in love with the underwater world. You could be one of them!
Contact us and we'll find the perfect dive for you
