Indonesia is famous for its vibrant, sunlit coral reefs, drawing recreational divers from across the globe to the waters of Raja Ampat, Komodo, and Bali. But for a select group of divers, the real magic happens well beyond recreational limits — deep in the world of technical diving in Indonesia.

1. Deepest Diver in Indonesia: Will Goodman

Will Goodman is a CCR Instructor Trainer who holds the record for the deepest open-ocean dive in Indonesian history. Operating out of Blue Marlin Tech on Gili Trawangan, Goodman's expertise lies in extreme-depth rebreather logistics and human performance under hyperbaric stress.

Goodman made diving history off the Gili Islands by descending to 290+ meters (estimated past 300 meters, where depth gauges maxed out) on an unmodified JJ-CCR. The dive required a 9-minute freefall into absolute darkness, battling cold water, severe currents, and High-Pressure Nervous Syndrome (HPNS) from the high helium concentration, followed by nearly 10 hours of decompression. Goodman is respected worldwide for his meticulous, engineering-focused approach to deep-support staging, custom bailout calculations, and team management.

2. Premier Cave Training Pioneer And Course Director: SF Chong

SF Chong is a PADI Platinum Course Director, TDI/IANTD Full Cave Instructor Trainer, and co-founder of the Indonesia Cave Diving Association (ICDA) . Based out of Sanctum Exploration in Sanur, Bali, Chong has logged over 10,000 dives and certified thousands of diving professionals.

Chong's core strength is bridging high-level instructor development with the unforgiving discipline of overhead environment diving. Rather than running a certification mill, his training focuses on high-stress cave navigation, gas planning under panic conditions, and zero-visibility line-following in flooded karst systems. Recently, he has been leading exploration trips into remote freshwater caves across Java, Sulawesi, and Sumatra while building standardized cave-diving safety protocols specifically tailored to Indonesia's delicate underground hydrology.

3. Pioneer of Technical Diving in Indonesia: Simon Liddiard

Simon Liddiard is the founder of Blue Marlin Tech, one of Indonesia's first dedicated technical diving outfits. A TDI Trimix Instructor Trainer, IANTD Advanced Trimix Instructor, and PADI Course Director with over 32 years in the industry, Liddiard has grown Blue Marlin into one of the country's largest dive operators, with locations across the Gili Islands, Lombok, and Komodo.

With more than 10,000 dives logged—over 300 of them beyond 100 metres—Liddiard set the record for the deepest solo trimix CCR dive at 150 metres during the sport's early pioneering years, and personally discovered several of the Gili Islands' now-iconic dive sites, including the Japanese WWII wreck and Simon's Reef, named in his honour. His contributions to the industry earned him PADI's "Outstanding Contribution to the Dive Industry" award, and he continues teaching technical diving courses across Gili Trawangan, the UK, and Gozo.

4. Distinguished Tech Instruction: Marc Crane

Marc Crane is a TDI and SSI Instructor Trainer and the founder of Tekdeep Asia , based in Bali. A professional diver since 1991, Crane specializes in Closed-Circuit Rebreather (CCR) training across multiple platforms—including the JJ-CCR, rEvo, Megalodon, Poseidon, and Triton—up to Advanced Trimix levels.

Crane is known as the "instructor's instructor". His forte is removing guesswork from technical diving through rigorous equipment diagnostics, decompression physiology, and diluent gas kinetics. Rather than focusing on simple skill execution, Crane tests divers with complex, multi-system failures at depth. His recent work includes mapping deep reef structures, supporting scientific research on marine megafauna, and leading deep wreck penetration expeditions across the Indonesian archipelago.

5. Frontier Diving: Robin Cuesta

Robin Cuesta, founder of Sulawesi Dive Trek in Baubau, Southeast Sulawesi, is a technical cave explorer and Triton CCR instructor. He represents true "frontier diving"—operating in areas completely devoid of dive shops or gas-blending infrastructure.

Cuesta's specialty is logistics in remote environments. He routinely hauls portable compressors, helium, oxygen cylinders, and rebreather gear through dense jungle to explore untouched freshwater sinkholes and cave systems. Recently, his team laid over 2 km of guideline in pristine, fossil-filled white-limestone caves on Muna Island. His work combines cartography, subterranean hydrology, and training local communities to support exploration.

6. A Career Built on CCR Education: Phillip Christoff

Phillip Christoff is an SF2 CCR Instructor Trainer based at Manta Dive on Gili Trawangan, with one of the broader teaching résumés in the region — TDI Instructor Trainer credentials spanning Advanced Nitrox/Decompression Procedures, DPV, and Sidemount, on top of his rebreather instruction. He joined the industry in 2014 with 50 logged dives and a rescue certification, and has spent the years since building on that range: full cave CCR certified in his own diving, expedition trimix dives to 145 metres on his SF2 eCCR, and experience running dual rebreather configurations.

Christoff's work sits at the intersection of education and documentation: alongside his instructional load, he's known locally for shark videography around the Gili Islands, using his rebreather background to get close, quiet footage recreational divers rarely see.

7. Marine Guardian and Cave Pioneer: Ayub Polii

Ayub Polii is a TDI Full Cave Instructor and SSI XR Cave Instructor at RocknRoll Divers in Bau-Bau, Buton, Southeast Sulawesi—one of the first Indonesian nationals certified to teach cave diving in the country. Alongside his instructional work, Ayub serves as a marine park ranger, pairing technical dive training with hands-on conservation work in the reefs and cave systems he helps protect.

Ayub's dual role as ranger and cave instructor is rare in the region: few technical divers combine frontline conservation work with the exploration and training needed to open up Sulawesi's cave systems safely. His work at RocknRoll Divers has helped establish Bau-Bau as one of Indonesia's emerging cave diving hubs, training a new generation of Indonesian divers to explore and protect their own waters.

8. Friendliest Tec-Rec Center for Beginners: Gili Divers

Located on Gili Trawangan and Gili Air, Gili Divers specializes in bridging the gap between recreational and technical diving. While technical diving can carry an intimidating, ultra-rigid reputation, Gili Divers has built its culture around approachability and patience without sacrificing safety.

Using TDI and RAID training frameworks, they offer entry-level tech programs—such as Sidemount, Advanced Nitrox, and Decompression Procedures up to 50 meters—supported by climate-controlled gear rooms and high-end hardware (Apeks, Tecline). They excel at turning recreational divers into confident decompression trainees in a welcoming island setting.

Much of that technical program is led by Clemence Le Flohic Gueguen, a RAID Deco 50 diver and JJ-CCR Mod2 mixed-gas diver who joined Gili Divers in 2021 to build out its dedicated technical diving department. Her approach leans on personalised, supportive training — the same approachable philosophy the centre is known for — helping recreational divers build the confidence to progress into decompression diving at their own pace.

Honorary Mention: Martin Slisans, YouTube Creator

Martin Slisans is a Bali-based technical diver, videographer, and Diver Propulsion Vehicle (DPV) specialist. Through his YouTube channel, Slisans documents the unvarnished realities of technical setups.

Rather than cinematic promotional edits, Slisans produces practical gear reviews (evaluating sidemount harnesses, DPV scooters, fins, and cameras under real task loading) and educational skill breakdowns (DSMB deployment, reel management, valve shut-offs). His recent content focuses on deep wall diving in Amed, Bali, scooter-assisted cave navigation, and gear configuration guides for aspiring tech divers. He is the founder of PADI IDC centre Ocean Dive League.

Choosing the Right Instructor for You

Every name on this list represents years — often decades — of accumulated expertise, but that doesn't mean any one of them is automatically the right fit for you. The people shaping Indonesia's tech diving scene each bring a different specialty, teaching style, and philosophy: some lean toward exploration and pushing depth records, others toward conservation, mentorship, or simply making decompression diving approachable for the first time.

The right choice isn't necessarily the most decorated name on this page. It's whoever's teaching style, location, and specialty actually line up with what you're trying to learn — and the only real way to find that out is to look around, ask other divers, and talk to a few before committing.

If you're ready to start that search, TecDiveTools' directory of Indonesia's dive centres and instructors lets you filter by agency, course, and rebreather support, so you can find someone actually teaching the path you want to take.