DEFY GRAVITY
Learn to Scuba Dive on Koh Tao
“The sea, once it casts its spell, holds one in its net of wonder forever” -Jacques Cousteau

Open Water 20
Learn to dive on Koh Tao! This is the scuba diving course that will make you an internationally certified scuba diver! No previous experience is required.

Try Dive
A Try Dive is a great way to experience scuba diving on Koh Tao if you’re short on time or would like to get a feel for before signing up for the Open Water 20 course.

Fun Diving
Twice daily excursions to scuba dive Koh Tao's beautiful dive sites. Whether you’re an experienced or newly certified scuba diver, our skilled dive leaders will guide you on an excursion through the world’s most varied ecosystem.
Why Choose Hydronauts?
RAID Instructors
Our experienced instructors are hand-picked, highly trained, and passionate about scuba diving. We tailor each course and dive to your unique needs.
Beachfront Diving Resort
Southwestern-facing property including a dive shop, hotel, training pool, cafe & restaurant, dive boat, and beach bar. We offer diving & accommodation packages for every budget.
Guaranteed Small Groups
We guarantee small groups of no more than four students to an instructor or dive guide so that you get the individual attention you deserve.
State-of-the-Art Equipment
We choose to dive and teach in Backplate & Wing BCD with a Long-hose, Short-hose regulator configuration favored by technical divers.
Dive Anywhere in the World
Upon completion of your RAID scuba diving course, you will be issued with an e-certification card that recognizes you as an internationally certified scuba diver.
Low Carbon Footprint
We make every effort to reduce our footprint and use of paper and plastic. All our course materials are hosted online giving you access for life.

Explorer 30 - Advanced
This is the next course after becoming a certified Open Water 20 scuba diver. Get extra training in buoyancy, navigation, deep (30 meters), and 2 elective dives.

Deep 40
Unlock some of the best dive sites and shipwrecks in the world by extending your depth certification to 40 meters.

Nitrox - Enriched Air
Do you want to extend your time allowed at a certain depth? Breathing Enriched Air Nitrox allows you to stay at depth for longer.
Ready to become a Hydronaut?
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“My favourite thing to do on this planet is to scuba dive” – Buzz Aldrin (Astronaut)
Read The Hydronauts Manifesto
Everyone dreams of a life of adventure and discovery. Many look to the stars in awe but at Hydronauts we recognise the wealth of undiscovered territory right here on planet earth.
Humanity knows less about the vast and varied ecosystem in our oceans than we do about outer space. And while we spend our nights staring up at the stars, at Hydronauts, we’ve chosen to fulfill our dreams a bit closer to home than your average stargazing traveler.
We’ve chosen to DEFY GRAVITY underwater.
Our mission is simple. Good people, good courses, good fun. All this while maintaining an unwavering dedication to quality so that every dive is over the moon throughout your time in our care.
With a small team of handpicked professionals, top-notch equipment, premium facilities and little extras in all the right places, we seek to design a diving experience unique to Hydronauts.
We focus on safety, conveying expert knowledge and tailoring each experience to ensure our divers and guests leave us wanting more.
Come DEFY GRAVITY with us.
