I STUMBLED, AND SWORE - BUT QUIETLY, to avoid waking anyone.
It was 4.30am. I pulled up just as I was about to step into the lagoon swimming pool, picked my way round it, hit a dead end and tried another route. Then I realised that, while wandering in the darkness, I had come full circle. I was back outside my room.
When I had enthused about doing a night-to-day dive, I hadnt reckoned on the resort grounds being unlit.
My room was quite near the dive centre, but a journey performed automatically by day was now a low-vis nightmare. Nervous of letting down the other early risers, and aware that dawn was looming, I took a deep breath, visualised and restarted.
The dive centre was a big complex, and this time I found it. I couldnt understand how I had missed it before. Now I could make out the long jetty, and Tasik Rias four dive-boats.
Our captain, jovial even at this hour, was fuelling one of the small open boats while Mehti, the wiry dive guide, prepared our kit. Guests are politely required to do nothing other than enjoy the diving in North Sulawesi.
My buddy, Katy, was a young English woman who seemed to spend an indecent amount of her life enjoying Indonesias underwater world, never missing a chance to dive.
We headed for nearby Critter Circus. With a hint of a chill in the air, hitting the 29°C water was like slipping into a bath. Torches on, we found sand at 18m. Almost immediately Mehti was pointing out two pieces of floating debris that revealed themselves in our circle of light as robust ghost pipefish.
Over 70 minutes we moved from sand to reef and back, crossing the border from night to day imperceptibly, until we realised that we no longer needed lights. We enjoyed a parade of blue ribbon eels with leafy snouts agape, friendly cuttlefish, a puffed-up yellow frogfish, fluttering harlequin shrimps, a tiny coconut octopus crawling out of its cockleshell duvet and countless jumpy anemonefish.
Towards the end of the dive, we even found a lone mandarinfish resplendent in its psychedelic colours, surprisingly still up after yet another orgiastic night.

SO ANOTHER DAY BEGAN in north Sulawesi, with the virtuous glow of the early riser looking forward to breakfast and another fine days diving.
In fact we did four more dives that day; five hours in the water, just like liveaboard diving. Fortunately Tasik Ria provides free nitrox, so doing this regularly neednt be a strain.
We stayed with the small boat to visit the most distant of the mainland sites, Coconut Corner, along the coast past the sinister-looking building where swallows construct birds nests for Chinese soup-eaters.
The site is a fine combination of muck-dive and impressive reef wall. Insatiable, we then dived three more local sites, including the Reefball, a collection of concrete spheres light as yet on coral but stuffed with cleaner shrimps willing to service any passing trade - including divers teeth and nails.
I believe I have all the makings of a chronic Sulawesi addict - and this was only my first visit. Rising before dawn is one symptom, and I still cant get the diving off my mind.
The revelation for me about the west side of the North Sulawesi peninsula, often referred to by the name of nearby Manado town, was that excellent muck-diving is to be had there alongside the offshore coral reefs I had expected.
Most days, we would take the 38m Aquatica dive-boat to the marine park around the island of Bunaken, a wide-angle visual feast.
The trip would take 45 minutes or so, though Tasik Diving staff eagerly anticipated the arrival any day of replacement boats capable of 20 knots.
Not that the crossing was a hardship, because Aquatica was comfortable, stable and well-equipped. We would do a couple of wall dives, have lunch aboard and sometimes explore the mainland sites for a third outing.

HERES A TYPICAL BUNAKEN DIVE. You descend onto coral outcrops and fin to the drop-off. People are pointing, and you can just make out an eagle ray on the edge of vision (typically 20m).
As you drop to 25/30m, a green turtle the size of a bubble car wanders by. A little further on, you find its twin sound asleep in a recess, and have ample time to enjoy the view. The wall soars above into turrets of vibrant coral and sponge, swept by glittering streams of yellow butterflyfish, angular red-toothed triggerfish and Moorish idols.
You might see a small blacktip shark cruising along the wall below, but much of the time you will be focused on the details - the full spectrum of nudibranchs, a long-nosed hawkfish here, a false stonefish there, and the photogenic occupants of white, green and bright orange anemones.
The anemonefish are feisty. Invade their territory and they dont just bob up and down looking cute. The first time I tried to photograph one I felt the impact as the bigger female launched herself Scud-like at my head. She left her mark.
You get used to checking every outcrop of bubble coral for purple-limbed hairy squat lobsters, or the orang-utan crabs that really do resemble miniature shaggy apes.
Its also worth checking whip corals for commensal shrimps.
The currents were usually mild on the walls, though I understand that they do get stronger, with occasional downcurrents - not so good on nitrox.
As for the mainland muck-dives, I soon surrendered my stern objectivity at the City Extra site. First time there,
I was amazed to see in the first five minutes both a mimic octopus and a flamboyant cuttlefish, a gleaming vision in red, plum and gold. Both species I had come to regard as semi-mythical, though they would become excitingly familiar during my Indonesian fortnight.
Mimic octopuses bury themselves quickly in the sand, but the sharp-eyed dive guides move fast, and a quick stir with the metal indicator wands they carry encourages the octopus to the surface, where it extends its spidery arms into bewildering shapes.
There is still debate about whether these creatures really do mimic, or just happen to resemble at times other sand-dwellers such as flounders, cuttlefish, and sea snakes, but they are fascinating to watch. I always had difficulty distinguishing them from wonderpuses, though Im told that the eye-stalks and head markings differ, and the wonderpus seems more golden-hued.
Flamboyant cuttlefish have recently been found to be the only toxic cuttlefish, as poisonous as the blue-ringed octopus also found off Sulawesi - no wonder they dare to flash such bright signals.
Coconut Cove is home to the rare Pontohi seahorse, named after a local guide who clearly had great eyesight, because this hydroid-dweller is the size of a pinkie fingernail clipping.
I could barely focus on it, because it also moved constantly and disappeared altogether when face-on. I could only shoot and hope.
I would also get to see a Pontohi in much shallower water on the second phase of my trip, when I transferred to Lembeh Strait. Only from the pictures did I appreciate that it was yellow, white and dumpy in profile, with tiny wings.

THE MUCK DIVES WERE REPLETE with sinuous seahorses, fabulous frogfish and much besides. Four divers per guide is the norm, and most people politely took turns to view.
Only once did irritation set in when, in comparatively low vis, a guest who had borrowed a guides metal stick spent an hour banging her tank at anything that moved. It sounded like a foundry down there.
Tasik Ria is a delightful resort, with 34 suites of rooms facing the private beach or dotted around the big pool, all shrouded in jungle vegetation. There is an excellent spa (how did I find the time) and the ever-smiling staff leave no stops unpulled, down to a choral send-off. Its not the last word in luxury, but everything you need is laid on at surprisingly keen rates.
Resident Manager Dan Green is a diver. A former chef from London, he has made his home in Sulawesi with his Indonesian wife Monica, an instructor, and their family.
He took me to the fishmarket in Manado one morning, and I noticed tiny blacktip sharks on offer, fishermens by-catch. In the past Dan has found sharks still alive here, bought them and carried them on his moped to return to the sea.
Monica has done the same, but on the local bus! They now have an arrangement to buy back any live sharks that turn up in the market.
Dans amiable personality is firmly stamped on the resort. He discreetly ensures that all the guests are getting what they want on their holiday.
The Tasik Diving centre, overseen by Brazilian Camilo Zuluaga, is similarly well-run, friendly and helpful.

I WAS SORRY TO LEAVE, but I was looking forward to sampling the eastern side of the peninsula.
We drove there, a highland tour that took in a 100% proof palm-wine distillery (I prefer Bintang beer); a volcanic lake of steaming vents and oddly multi-coloured water; Lake Tondonau, where golden carp are served straight from the water for lunch; and a meat market where batwing and dog are among the delicacies on offer.
From the large port town of Bitung, a tiny road winds into precipitous hills. Along here are the growing number of resorts serving those eager to dive the mile-wide strip of Sulawesi Sea between here and Lembeh island.
Danish brewers dont run dive resorts, but if they did, theyd do well to study how Kasawari Lembeh Resort does it.
Unlike the bigger Tasik Ria, this is
no place for non-divers. Here you boat-dive, emerge to hot and cold towels, fruit and drinks, and return to base for bodily refuelling. Repeat four or five times a daily, each dive lasting an hour to 80 minutes, and fight a losing battle with your waistline day after day.
Your comfortable villa has everything you could reasonably desire, including wi-fi. The dive centre is spacious and well-equipped, ditto the camera room.
The staff are set to charm factor 10, and there are many staff per guest. If you like diving, marine-life photography and stuffing your face, youll like this place. If you want night life you wont - everyone retires early, all dived out.
Kasawari is run by Nuswanto Lobbu, one of the pioneers of Lembeh muck-diving in the mid-90s. Ali Umasangadji, who comes from Ambon, has worked with Nus for years, and fortunately he was my dive guide for the week. If a rare creature is hiding out in Lembeh Strait, Ali knows where to find it.
The water is just getting cooler - thats when the frogfish start coming in, he told me, conjuring an image of dumpy muppets bowling through the water to cool off in 27° Lembeh waters.
But already in July we were seeing frogfish everywhere - big gnarly yellow and green ones posing together on red sponges with no attempt at concealment, and pink, orange and brown ones from gooseberry to plum size living among debris in the grey sand.
My favourite was a baby clown frogfish at the fabulous sea-mount Angels Window. Tiny and bleach-white, it sported a long lure and red and orange circus make-up. About the only variant we didnt see was a hairy frogfish, but I had already seen one off Manado.
Without an Ali, I would have missed the smaller, best-camouflaged denizens of Lembeh Strait. You could almost order your pygmy seahorse - he could find both red and yellow varieties.
Only on our last dive at 30m or so with, unusually, a current getting up, did our quarry almost outwit him, but he found it in the end. Its all worth it when you blow up your images of these tubercular seahorses, tails wrapped around the Muricella gorgonians with which they blend.
The same applies to ornate ghost pipefish, cunningly disguised to resemble their host crinoids; the weird green Halimeda variety, with its cactus-like appearance; and the smooth red velvet ghost pipefish.
You dont need expert eyes to spot everything at Lembeh. Many of its denizens resemble vagrants dressed in layers of shabby clothing, trundling along or resting wherever shelter presents itself - natural or man-made.
Many of the extensive scorpionfish family in particular seem to have let themselves go.
Resist the urge to brush them down before taking their picture, because touching such toxic creatures would only end in tears. But when the likes
of demon stingers, oriental flying gurnards or dragon sea-moths spread their wings, the drabness is suddenly transformed into scintillating displays of colour and finery.

A PRIZED SCORPIONFISH among photographers is the weedy Rhinopias frondosa. There was nothing shabby about the brilliant crimson specimen we saw several times at the Aer Panga 2 site.
Also hard to miss are the many blue-spotted rays, sea-snakes and snake eels, brilliantly coloured mantis shrimps and cuttlefish - common, flamboyant and bobtail. They dont rush off, either.
Finding your next creature becomes an obsession. It wasnt deep enough for narcosis, but on the last of a long series of dives on Lembeh seabeds, I did find it hard to shake the illusion that I was scouring a ploughed field for a missing set of car-keys.
If the muck-diving at Manado had been a revelation, I was as surprised to find that Lembeh was not just the grey, trash-strewn seabed I had expected, but boasted its own hard and soft coral landscapes - not on a Bunaken scale, but colourful, healthy and buzzing with life.
There were anemones everywhere on these dives, with anemonefish and equally twitchy damselfish lording it over them. Schools of tiny Banggai cardinalfish also favoured these habitats, and glorious nudibranchs of every denomination abounded, including big ones like the bright yellow banana nudi.
On one occasion atop a pinnacle, I watched a sting ray vanish into a tunnel, went round to see it come out the other side and found instead a large octopus, evidently displaced by the ray.
I had missed the mandarinfish evening dives at Manado, so I attended a couple of these touching events at Damisa Point off Lembeh Island.
We got there early to bag the best spots, at the lower end of the coral head they inhabit at about 6m, and settled down for the next hour to watch these tiny dragonets get increasingly aroused.
As darkness falls, the guides wrap coloured cloth round their torches to turn the scene into a red-light district, and it all kicks off.
Pairs of mating mandarinfish suddenly rise off the coral head like bubbles, in an ecstasy of coupling.
We voyeurs press the shutter and pray that the shot is captured before the two fish explode apart in a tiny shower of sperm. The guides would count up to 30 of these magic moments.
Its yet another compelling pastime, and this is what happens in North Sulawesi - you check your pictures each night and think, OK, but perhaps we could go back just one more time tomorrow...
So addictions begin. See the factfile below for support groups.

FACTFILE
GETTING THERE: Steve Weinman flew with Singapore Airlines to Singapore and SilkAir to Manado. You can get a tourist visa there. Though its a long flight, a low-price option is to travel with budget airline Air Asia via Kuala Lumpur
DIVING & ACCOMMODATION: Manado: Tasik Ria Resort Spa & Diving Centre, www.tasikria.com. Lembeh Strait: Kasawari Lembeh Resort, www.kasawari-lembeh.com
WHEN TO GO: Any time. On the Lembeh side marine life is said to be most plentiful from July to December.
LANGUAGE: Indonesian, but English widely spoken.
MONEY: Rupiah, US $ (travellers cheques rarely accepted).
HEALTH: Usual inoculations, anti-malarials.
PRICES: A six-day, seven-night all-inclusive Tasik Ria Dive Package, with full-board accommodation and three boat dives a day, costs US $983 a head (around £600 at the time of writing). Add flights (£670-£850) and transfers ($15). Tasik Diving organises special trips to Lembeh Strait or Bangka for $45 per person with any package taken. A six-night/ seven-day all-inclusive full-board package in a deluxe villa at Kasawari, with 15 guided boat dives plus jetty and night dives and tranfers costs $1570 (£950). Add $102 for nitrox.
TOURIST INFORMATION: www.indonesia-tourism.com