Koh Daeng/Red Island - Similan Islands
Koh Daeng, or Red Island, sits a little apart from the main Similan group, and we often find it’s a good spot for a relaxed second dive. The maximum depth here is 14m, making it ideal for newer divers or those who just want to soak up the shallows without worrying about deco limits. The topography is mostly gentle slopes of hard coral, punctuated by some impressive bommies that are home to plenty of anemonefish. Look closely, and you’ll likely spot banded sea snakes winding their way through the reef, or a sleepy cuttlefish tucked into a crevice. It’s not a thrill-a-minute site, but it’s consistently pleasant and reliably pretty, especially when the sun is high and the colours really pop.
- Location
- Similan Islands, Thailand, Southeast Asia
- Coordinates
- 8.006300, 98.755000
- Maximum Depth
- 14m
- Difficulty
- Beginner
Marine Protected Area: Hat Noppharat Thara-Mu ko Phi Phi
Best Time to Dive in Similan Islands
The warmest water temperatures in Similan Islands occur in May, averaging 30.8°C. The coolest conditions are in January at 28.6°C.
Monthly Water Temperatures
- January: 28.6°C
- February: 29.0°C
- March: 29.6°C
- April: 30.6°C
- May: 30.8°C
- June: 29.9°C
- July: 29.6°C
- August: 29.3°C
- September: 29.0°C
- October: 29.0°C
- November: 29.2°C
- December: 28.7°C
Nearby Dive Sites in Similan Islands
- 8 mile rock
- Andaman Scuba
- Anemone Reef (reef)
- Anita s reef - 5-20m (reef)
- Anita's Reef - 10-25m (reef)
- Anti gravity Divers
- Ao Kon Ka Re
- Ao Nui - 17m
- Ao Sane - 5-18m (reef)
- Ayara Bay - 17m (reef)
- Banana Bay - 5-20m (reef)
- Barracuda Rock - 20m (pinnacle)
- Batfish Bend - 10-28m (drift)
- Bay 1 / Ao Ter (reef)
- Beacon Beach
Nearest Dive Centres to Koh Daeng/Red Island
- ABC Phuket Diving
- Activity and diving centre
- Adang Sea Divers - SSI
- All 4 Dive - PADI
- All4Diving® Phuket - ["PADI"]
- Amazing Phuket adventures - SSI
Marine Life in Similan Islands
Home to 183 recorded species including 127 reef fish, 38 hard corals, 9 seagrass & algae, 4 sharks & rays, 2 other, 1 octopus & squid.
Notable Species
- Whale Shark (Rhincodon typus) - Sharks & Rays
- Staghorn coral (Acropora kosurini) - Hard Corals
- sorrah shark (Carcharhinus sorrah) - Sharks & Rays
- Staghorn coral (Acropora indonesia) - Hard Corals
- seagrass (Halophila ovalis) - Seagrass & Algae
- Dusky Parrotfish (Scarus niger) - Reef Fish
- Bicolor Blenny (Ecsenius bicolor) - Reef Fish
- Moluccan cardinalfish (Ostorhinchus moluccensis) - Reef Fish
- Staghorn coral (Acropora secale) - Hard Corals
- Staghorn coral (Acropora valida) - Hard Corals
- Staghorn coral (Acropora hoeksemai) - Hard Corals
- cymodocea (Cymodocea rotundata) - Seagrass & Algae
- Herringbone butterflyfish (Chaetodon triangulum) - Reef Fish
- Dollfus's octopus (Amphioctopus aegina) - Octopus & Squid
- Clown Tang (Naso lituratus) - Reef Fish
- Staghorn coral (Acropora solitaryensis) - Hard Corals
- Species code: Ea (Enhalus acoroides) - Seagrass & Algae
- Blue-scaled wrasse (Cirrhilabrus cyanopleura) - Reef Fish
- Argus Grouper (Cephalopholis argus) - Reef Fish
- Staghorn coral (Acropora austera) - Hard Corals
Recommended Packing List for Koh Daeng/Red Island
Based on average water temperature of 29.4°C, currents 7 cm/s.
- Shorty or Rashguard - warm 29°C water needs minimal exposure protection
- Mask - essential for every dive
- Fins
- BCD - buoyancy compensator
- Regulator - your most safety-critical piece of gear
- Dive Computer - tracks depth, time, and NDL
- Surface Marker Buoy (SMB) - essential for boat pickups
- Dive Torch - useful for crevices and colour at depth
- Underwater Camera - capture your diving memories