Halcyon Symbios: rebreather training now available across six agencies

Halcyon has announced a major expansion for its chest-mount closed circuit rebreather. The Halcyon Symbios is now officially supported by six international training agencies: GUE, IANTD, PADI, SNSI, SSI, and TDI.

For underwater photographers seeking silent, bubble-free encounters with marine life, broader instructor availability is often the key to considering a rebreather setup.

Unlike traditional back-mounted rebreathers that replace standard diving cylinders and buoyancy compensators entirely, the Symbios is designed to be worn on the diver's chest.

This design offers distinct advantages: - It frees up back space for streamlined sidemount or stage bottles. - It can serve as a primary lightweight rebreather or as a dedicated bailout CCR during deep exploratory dives. - It runs on the Guardian r-OS digital architecture with vibrating head-up alerts.

Until recently, training on the Symbios was primarily conducted through GUE. Expanding certification pathways to PADI, TDI, SSI, IANTD, and SNSI broadens access significantly.

This brings: - More certified instructors across Europe, the Americas, and Asia. - The ability to train through your existing agency without cross-certifying from scratch. - Greater competition and easier access to demo units in regional dive hubs.

To compare technical gear configurations and find suitable wings, explore our diving equipment comparison tool and our guide on technical buoyancy control systems.

Rebreather diving demands rigorous pre-dive checks and maintenance. In June 2026, Halcyon issued a mandatory safety inspection notice regarding oxygen Manual Add Valves following isolated thermal events. Thorough training and meticulous pre-dive checklists remain non-negotiable.

Mastering buoyancy and stealth underwater is at the heart of our curriculum in the AquaExposure training program.