From South to North: An Andaman Sea Diving Adventure
From rugged cliffs rising out of turquoise water to remote reefs pulsing with life, the Andaman Sea always rewards those who explore it patiently.
This week’s itinerary took us on a beautiful journey from the limestone islands of the South Andaman up to the vibrant reefs of the North Andaman. From Koh Phi Phi and Koh Lanta to the Similan and Surin National Parks, the route offered a wonderful contrast between dramatic pelagic encounters and intricate macro life hiding in the reefs.


Day 1 – From Phuket to Koh Phi Phi National Park
We departed from Charter Marine Pier in Phuket together with our Dive Buddy guests from Israel and began sailing towards the famous Phi Phi Islands. Phi Phi National Park is known not only for its spectacular limestone cliffs rising straight out of pristine waters, but also for its vibrant coral reefs and sheltered bays that host a wide diversity of marine life. After a relaxed evening at anchor beneath towering cliffs, everyone was eager to begin diving the following morning.
Ready To Dive | Vélika Marquis
Day 2 – Koh Phi Phi National Park & Koh Lanta National Park
Our check dive at Koh Bida Nok immediately reminded us why this site is so popular. Blacktip reef sharks cruised calmly along the reef edge while a tigertail seahorse and a ghostpipefish provided the first macro highlights of the trip. Flounders rested on sandy patches while feather seastars walked slowly across the reef. Schools of snappers gathered around coral heads and several Phyllidia species appeared alongside Hypselodoris bullocki, Hypselodoris iacula and purple-spotted Hypselodoris.
Purple urchin shrimps hid among spines, while banded sea snakes moved gracefully between rocks. A snowflake moray eel peeked from its shelter and Goniobranchus fidelis, Flabellina rubrolineata and decorator crabs added colourful details to the reef. Around us swam coral groupers, peacock groupers, powder-blue surgeonfish, threadfin butterflyfish and schools of yellowback fusiliers moving through healthy coral gardens.





The second dive took place in the calm Koh Haa Lagoon. A giant moray eel rested beneath coral bommies while juvenile clown triggerfish hovered nearby. A passing blacktip reef shark cruised over the sand as blue dragons glided along the reef. Macro highlights included Glossodoris rufomarginata, Halgerda tesselata, Janolus sp., Andaman jawfish and cardinalfish carrying eggs in their mouths. Bluestreak cleaner wrasse performed their cleaning dances while bicolor blennies watched from coral holes. Squat shrimps and lobsters shared rocky crevices as razor wrasse flashed across the reef.
The third dive brought us to the famous Koh Haa Cathedral, where shafts of sunlight illuminated the cavern. A juvenile hawksbill turtle glided slowly through the entrance while nudibranchs decorated the walls: Glossodoris hikuerensis, Bornella anguilla, Goniobranchus reticulata, Halgerda tesselata, Hypselodoris sp. and Glossodoris atromarginata. Skeleton shrimps clung to hydroids and a tiger cowrie rested beneath a coral ledge.



Our night dive at Hin Daeng transformed the reef into a hunting ground. A giant moray eel prowled through the darkness while red reef crabs and ornamental spider crabs emerged from hiding. A red abalone rested on the rock and comb seastars stretched across the reef surface. Batfish and great barracuda passed slowly through the torchlight while Clark’s anemonefish guarded their eggs. Anemone hermit crabs and anemone crabs shared their hosts and a splendid red spooner crab waved its arms across the reef. Nearby, an ornate sap-sucking slug (Elysia) grazed along the coral.
Day 3 – Koh Lanta National Park
The morning began at Koh Rock, where colourful reefs hosted large schools of parrotfish and wrasses. A rare big feathertail stingray glided across the sandy bottom while a mimic phyllidia nudibranch rested beside Hypselodoris jacksoni. Stonefish blended perfectly into the reef and a banded sea snake moved slowly between coral heads. Clark’s anemonefish nurtured their eggs while anemone crabs guarded their homes.
Goniobranchus geminus, script flatworms, bluefin trevally and dragonets appeared across the reef. Lobsters hid beneath rocks while hairy shrimps, whip coral cowries, Flabellina rubrolineata, blue dragons and Ceratosoma tribolatum added a beautiful macro layer.





At Hin Daeng, the reef exploded with life. Juvenile emperor angelfish shimmered in yellow and blue while tiger cowries rested beneath coral ledges. Barracudas circled above the reef while Goniobranchus reticulata, Goniobranchus geometrica and spotted Hypselodoris decorated the walls. Giant moray eels and bartail morays hid among cracks where masked porcupinefish shared shelters with banded boxer shrimps. Batfish cruised past while turtles, ghostpipefish, yellow-margin moray eels and mackerels passed through the blue.
The third dive at Koh Haa Neua – the Chimney – delivered exceptional macro life. Glossodoris cincta, ghostpipefish, tiger egg cowries, Cuthona sibogae, Bornella anguilla, ornate sap-sucking slugs and Moridilla brocki decorated the walls. Hypselodoris maculosa, Hypselodoris whitei, Caloria indica and bicolor flabellina added vibrant colours while lobsters hid between rocks. Schools of yellowback fusiliers and lunar fusiliers swirled above the reef together with copperband butterflyfish, Indian sailfin tang, coral grouper and blue-striped snappers.
After the final dive, we began our northern crossing towards the Similan National Park.



Day 4 – Similan National Park
Our first dive took place in Honeymoon Bay, where a large Jenkins ray rested peacefully on the sandy bottom.
At Tuna Wreck and Hideaway Reef, excellent visibility revealed giant sweetlips, a curious Napoleon wrasse and a delicate pygmy pipehorse. The psychedelic batwing slug added colour to the reef while schools of yellowback fusiliers, twinstripe fusiliers and blue-striped snappers swirled above the wreck. Coral groupers, powder-blue surgeonfish, threadfin butterflyfish and oriental sweetlips patrolled the reef.



At West of Eden, the macro world shined once again. A psychedelic batwing slug and kissing pygmy pipehorses were highlights, while a mantis shrimp watched from its burrow. Squat shrimps, darkspotted flatworms and Xenia crabs decorated the reef and MacKosker’s flasher wrasse flashed bright colours. Pipefish hovered in the current and during our surface interval a giant green turtle swam right beside the boat to greet us.
Green Turtle Visits the Boat | Camille Rovillain
The night dive at Honeymoon Bay was full of activity. Trevallies hunted among schools of small reef fish while porcupinefish and pufferfish cruised slowly through the sand patches. Barracudas passed in the distance while red reef crabs carrying eggs moved across the reef. Moray eels hunted actively and sleeping parrotfish and wrasses rested beneath coral ledges.


Day 5 – Similan National Park
At Deep Six, a whitetip reef shark cruised the reef while a turtle swam past granite boulders. An octopus shifted colours across the rocks while blue dragons and psychedelic batwing slugs decorated the reef. Powder-blue surgeonfish, copperband butterflyfish, oriental sweetlips and schools of neon fusiliers filled the water column.
Elephant Head Rock delivered dramatic granite formations. A blue ribbon eel waved from its burrow while an octopus explored the reef. Bornella anguilla and blue dragons appeared on the rocks beside an adult yellow boxfish. Giant trevallies and bluefin trevallies cruised through the arches while surgeonfish and oriental sweetlips gathered around coral heads. A giant moray eel watched divers from its cave.


At Three Trees, a school of barracuda hovered in the blue above giant sweetlips and garden eels. Blue-spotted Kuhl’s rays rested on the sand and a giant barrel sponge dominated the reef structure. Schools of blue-lined snappers, yellowback fusiliers and scissortail fusiliers moved constantly across the reef.
That evening’s blackwater dive was spectacular: male and female paper nautilus drifting gracefully, juvenile porcupinefish, squirrelfish larvae, squids, flounders and even a flying gurnard drifting through the beam of our lights.









Day 6 – Similan National Park
At Koh Bon Ridge, schools of barracuda circled above giant trevallies and bluefin trevallies. Damselfish, butterflyfish and two-tone dartfish hovered above the reef while Clark’s anemonefish guarded their homes. Titan triggerfish, redtooth triggerfish and the distinctive “WiFi triggerfish” moved across the reef alongside pajama surgeonfish. Nudibranchs such as Haminoea cymbalum, Chelidonura hirundinina and Chelidonura punctata decorated the sand while a banded sea snake slithered past. Andaman sweetlips hovered near coral ledges.


Koh Tachai Plateau was spectacular. Blacktip sharks and Jenkins rays cruised across the plateau while a massive school of chevron barracuda filled the blue. Giant trevallies, bigeye trevallies, dogtooth tuna and rainbow runners hunted actively. Giant marble groupers rested near coral bommies while yellowback and neon fusiliers formed massive clouds above the reef. A juvenile hawksbill turtle swam past and clown triggerfish hovered near coral heads while whip coral gobies hid among gorgonians.


On the third dive from the third pinnacle to the main plateau we encountered two more Jenkins rays, a curious Napoleon wrasse and two octopuses flirting among the rocks. Giant trevallies and bluefin trevallies cruised through dense schools of yellowback fusiliers while giant moray eels and batfish watched from the reef.
The night dive on Koh Tachai Reef revealed Glossodoris, Elysia species and Halgerda tesselata. A blacktip reef shark cruised through the darkness while a giant moray eel hunted along the reef.


Day 7 – Surin National Park
We returned to Richelieu Rock for three spectacular dives. Purple soft corals covered the pinnacle while glassfish formed shimmering clouds around the rock. Harlequin shrimps, ghostpipefish and thorny seahorses delighted macro lovers while Durban dancing shrimps, orange-spotted pipefish and cleaner pipefish filled the reef with activity.
Giant trevallies and the famous Richelieu “gang” — rainbow runners, trevallies and longnose emperors — hunted through the schools of fish. Barracudas formed impressive formations including chevron, yellowtail and pickhandle barracuda. Peacock mantis shrimps, banded boxer shrimps and blue-legged boxer shrimps decorated the reef while giant moray eels and a zebra moray eel emerged from their holes. Scorpionfish and devil scorpionfish rested on the reef while batfish and juvenile emperor angelfish cruised nearby.





Our sunset dive at Ao Pakard (Cabbage Bay) revealed a vibrant coral reef. A hawksbill turtle swam slowly past while schools of juvenile barracuda hovered above the reef. Sailfin tang surgeonfish grazed alongside yellow saddle goatfish, angelfish and triggerfish. Kuhl’s blue-spotted stingrays rested on the sand while blue dragons, juvenile scorpionfish and juvenile mantis shrimps appeared among coral rubble.
Day 8 – Return to Ranong
The final morning began at Torinla Pinnacle, where Koran angelfish swam alongside surgeonfish, butterflyfish and giant moray eels. A whitetip shark slept beneath a rock while a school of bumphead parrotfish passed slowly through the reef. Kuhl’s blue-spotted rays glided across the sandy patches and a bright yellow “Pikachu” nudibranch delighted photographers.
The Richelieu Rock “Gang” | Udi Nehab
For the final dive at Richelieu Rock, the reef delivered a grand finale. The gang returned once more: trevallies, longnose emperors and a ball of jacks swirling through the water column. Barracudas formed impressive schools while juvenile clown triggerfish and juvenile emperor angelfish hovered over the reef. Thorny seahorses, ghostpipefish and tiger cowries with their eggs decorated the coral. Hypselodoris decorata, dark-margin glossodoris and blue dragons added colour while peacock mantis shrimps guarded their burrows. Schools of yellowback fusiliers, lunar fusiliers and manylined fusiliers filled the water column above coral groupers, copperband butterflyfish and powder-blue surgeonfish.
Soon after surfacing, we began sailing back towards Ranong — closing another unforgettable Andaman adventure aboard the MV Smiling Seahorse.
Until the next tide brings us together again — dive well, dive aware, and see you soon fellow divers.



Photography by Franck Fogarolo, Itai Grisaru, Udi Nehab and Vélika Marquis
Videography by Camille Rovillain and Vélika Marquis