Bida Nai
Koh Phi Phi · Thailand
The smaller of the twin Bida islets, with a shallower reef profile that makes it ideal for less experienced divers and night dives. Hard coral coverage on the north face is exceptional — fields of staghorn and brain coral that survived the 2010 bleaching event better than most Andaman sites. Titan triggerfish are territorial in the shallows; blue-spotted stingrays cruise the sandy channels between coral heads.
Conditions
Depth
5 to 28 m
Open water and up
Current
Often strong
Can pick up on the edge
Visibility
5 to 12 m
Clearest in the calm season
Water
26 to 30°C
3mm wetsuit
Month by month
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Water (°C) | 27 | 27 | 28 | 28 | 28 | 28 | 27 | 27 | 27 | 27 | 27 | 26 |
| Vis (m) | 18 | 18 | 18 | 15 | 8 | 5 | 5 | 5 | 5 | 8 | 15 | 18 |
| Current | Gentle | Gentle | Gentle | Moderate | Strong | Strong | Strong | Strong | Strong | Moderate | Gentle | Gentle |
Your chances of seeing each animal
Clownfish
Last confirmed Feb 20, 2026 · 24 records
Very likely
Most dives
Moorish Idol
Last confirmed May 25, 2026 · 34 records
Very likely
Most dives
Giant Moray Eel
Last confirmed Feb 27, 2026 · 25 records
Very likely
Most dives
Titan Triggerfish
Last confirmed Feb 15, 2026 · 5 records
Very likely
Most dives
Blacktip Reef Shark
Last confirmed May 25, 2026 · 37 records
Likely
About 6 in 10 dives
Blue-ringed Angelfish
Last confirmed Mar 5, 2025 · 4 records
Likely
About 6 in 10 dives
Staghorn Coral
Expected
Known here, not yet in recent logs
Brain Coral
Expected
Known here, not yet in recent logs
Gear