Green Rock

Best time to dive

January to December; March to May

What you might see

• BarracudaLikely
• Moray eelLikely
• NudibranchLikely
• Sea turtleLikely
• Whale sharkPossible

Sightings are seasonal probabilities, not promises - even in peak season nature does its own thing.

Certification & difficulty

Advanced Open Water - advanced conditions (currents/depth); dive within your training.

Snorkelling

Not a snorkel site - Not a documented snorkel site (boat-only, current-exposed boulder field); nearby Koh Nang Yuan itself has separate shallow snorkel spots

Safety notes

Aggressive nesting triggerfish (Apr-May) near sandy trigger pits; variable/strong currents; tight swim-throughs require good buoyancy; entanglement risk in narrow caves

Permits & fees

No National Marine Park fee (Koh Tao outside National Park system); only the small island-wide municipal pier fee

Permits and operators change - confirm before booking.

Location

Nearest hub: Koh Nang Yuan