Dear Fellow Diver:
“The hardest part of diving the Devil's Throat is getting past the tonsils.”
  Those were Jeremy Anschel's words before we backrolled off his Living
  Underwater dive boat at Punta Sur, Cozumel. Once on the bottom, he led my
  buddy and me through a narrow hole into a cramped black cave — the devil's
  tonsils. Barely keeping track of his fins in the murk, I followed Jeremy
  until I spotted light coming from below us. Jeremy slid over the edge of
  the cave at 90 feet into a tunnel — the devil's throat — and began descending
toward the light. I followed him down.
 At 127 feet I exited into blue-water with 100-foot visibility. Finally
  turning on my dive light, I ignited a riot of color on the lush, overgrown
  walls. Jeremy took me into another cave, the Cathedral, with a natural white
  coral cross on one wall. We exited and he pointed out the Devil's Eyes, two
openings in the wall with sunlight streaming spectrally through them.
 By that point my computer had gone into decompression mode. With Jeremy
  leading, my buddy and I wove our way slowly up the wall until my computer
  was out of deco. A half-dozen barracudas entertained us as we glided along
the reef top on our final 15-foot safety stop.
 The Devil's Throat has become one of Cozumel's signature dives. Not all
  dive operators go there, partially because of its remote location near the
  southern end of Cozumel's western shore. But, it's also a decompression
  dive. That's one reason I'd chosen Living Underwater, which offers a unique
  combination of advanced diving with “valet” service, meaning maximum adventure
  with minimum hassles. They also use 120 cu. ft. and 95 cu. ft. steel
  tanks for extended bottom times. My Devil's Throat deco dive, for instance,
  had lasted 64 minutes.
Shortly after arriving at the Hotel Cozumel & Resort in early January, I
  met Jeremy in the lobby to fill out his paperwork and so he could collect
  my gear (even wetsuit), and have it ready on his boat the following morning.
  The hotel, formerly called Las Brisas, is on Avenida Rafael Melgar, the
  waterfront road that leads into the picturesque town of San Miguel. It's a
  full scale resort, with Cozumel's largest pool, a stage for outdoor entertainment,
  tennis courts, ping pong tables, and workout equipment and can be
  booked on an inclusive or European plan basis. It allows pickups by other
  dive operators. To get the beach, I strolled through a tunnel under the
  Avenida to the Club de Playa. On the beach, the club has its own bar, buffet,
  small shallow pool, lounge chairs, and steps to the water by a boat
  dock. Here, Dive Paradise has its own boats and offers gear lockers and
  fresh water rinse facilities.
 That night my buddy and I ate in the Hotel Cozumel's sparsely patronized
  dining room. Our meals were eclectic and hearty but undistinguished, and the
  only white wine (Calafia, from Baja California) drove my wine snob buddy
  into the frosty embrace of a Dos Equis. Our spacious, air-conditioned room
  had two double beds, a writing table with two wicker chairs, and a secure
  sliding-glass door to a balcony facing the ocean, with dive gear drying pegs
  and a table and chairs. Our cable TV pulled in some programs in English. I put down a deposit for a key to the safe in our closet and another for the
  TV remote and settled in. Our stuff stored easily in 3-drawer bureaus, as
  well as the closet.
 The next morning at 8:00 a.m., Jeremy and his captain, Francesco, were
  waiting at the hotel dock in Living Underwater's 7-passenger, 28-ft. dive
  boat, powered by twin Yamaha 150 hp outboards. We headed out to dive while
  most other operations were still loading passengers and gear. Since we were
  his only guests, Jeremy asked for requests, and I responded with “the splendid
  toadfish,” the notoriously reclusive creature endemic to Cozumel. “How
  many would you like to see?” Jeremy asked, then ordered Francesco to take
  us to a site called Tormentos.
The speedy LU boat is equipped with a fly-bridge and small square shade
panel amidships. There's a tiny forward cabin for dry storage, but no head.
Jeremy gave us cushions for the bumpy, and sometimes wet, ride. My tank had
been set up, so I slipped on my wetsuit and Francesco helped me into my BCD
with tank. With Francesco's help, I stood with the big 120 cu. ft. steel
tank, awkwardly raising it over a lip on the gunwale. Then my buddy and I
backrolled into the water.
Jeremy led us on a gentle drift in less than one-knot current. A 3-
  1/2' foot barracuda hovered under a ledge. A 5' spotted eagle ray had a
  piggybacking remora, and they were followed by a 3' dog snapper. I saw huge
  gray angels, a motorcycle gang of durgons in their shiny black jackets,
  and gruff bi-color damselfish defending their territory like Nemo wannabes.
  A sand diver darted out of his hole to attack Jeremy's finger. And Jeremy
  pointed out one splendid toad in a hole. When I signaled that I was down
  to 700 psi, Jeremy uncoiled a surface marker buoy so Francesco could follow
  our drift. As we coasted along, he slowly reeled in at 5' increments until
  we reached our safety stop depth. Toward the end of the 84-minute dive, I got chilled, despite
  the 79° F. water. That,
  I realized, was one
  downside of using larger
  tanks. Another? After
  my second day of diving
  with the heavy steel 120,
  my back began to ache.
  The discomfort continued
  throughout my stay and
  lasted for two months
  after returning.
 Jeremy's routine
  includes settling on the
  sand for several minutes
  at the beginning
  of most dives to crank
  down everyone's metabolism.
  Then, the final 15
  minutes or so are spent
  drifting under the SMB,
  usually several feet
  above the reef. So we
  logged bottom time, but not all of it quality time. To further increase
  bottom time, he overfills his 2,400 psi-rated tanks to 3,000 psi to give
  his divers 25 percent more air. This practice alarmed me, as did signs of
  rust I spotted above the tank boots. He dismissed my concerns, but further
  research convinced me that he may be taking greater risks than he realizes
  (see sidebar).
 Upon reaching the side of the boat, we hung onto a nylon line and my
  buddy doffed her weight belt and scuba rig, passing them up through a gate
  to Francesco while Jeremy climbed on board. Then she worked her way along
  the line back to the ladder near the stern, where she handed up her fins
  before climbing aboard. Francesco removed the BCD and regulator from her
  tank before taking mine, and with the combination of current and surface
  chop, I was frequently banged against the boat while waiting my turn. I
  couldn't imagine going through this routine with seven divers.
 On board, Jeremy offered warm towels, bottled water and fruit, and
  fleece-lined parkas. Then, off for a long surface interval at a beach club
  called Playa Corona to order lunch. Ever the doting host, Jeremy brought
  fish ID books to the table and answered my questions with great patience. A
  native of Minnesota, he had worked for Cozumel's Aldora Divers and then for
  Living Underwater, which he bought three years ago.
 On our afternoon dive at Las Palmas, Jeremy produced three splendid toadfish,
  one with his gaudy, painted face fully visible. I also spotted tile
  fish, box fish, slipper lobster, a fire worm crawling on the sand, a ton of
  Pixar-pretty tropicals, and arrow crabs lounging in vase sponges.
 On another day at Palancar Bricks, I tooled along a glorious jumble of
  hard and soft corals studded by a rainbow of sponges and faceted by grottoes,
  tunnels, and overhangs. This site was more sumptuous than anything
  I've seen in Grand Cayman or the Bahamas, and reminded me of Manta Wall at
  Belize's Lighthouse Reef. When other divers emerged from a swim-through, we slipped through a cut to the side
  of the reef they had just vacated.  They
  approached two hawksbill turtles, so
  Jeremy signaled us to hover, and soon
  they spooked one of the turtles toward
  us — seems he knows diver behavior as
  well as he knows his marine life.
They
  approached two hawksbill turtles, so
  Jeremy signaled us to hover, and soon
  they spooked one of the turtles toward
  us — seems he knows diver behavior as
  well as he knows his marine life.
 Palancar Caves offered equally spectacular
  topography as Jeremy led us
  through an underwater fun-house of swimthroughs.
  In the sand around the caves
  he found a banded jawfish and a 16-inch
  furry sea cucumber, which he stroked
  into such a relaxed state we were all
  able to handle and caress its limp body,
  studded with thousands of suckers on
  its underside. The ever-popular Palancar
  Reef has so many great sites I could
  have dived it exclusively. I was disappointed, however, in one dive, the
  well-advertised C-53 wreck (or “Felipe Xicotencatl”), a 200-foot minesweeper
  intentionally sunk in 2000. It has little marine encrustation or vertebrate
  life and the rooms have been so “sanitized” for safe diving, it was impossible
  to tell what most of them had once been.
 We did eight dives in four days with Living Underwater, sometimes too
  pooped to do any more (the longest, at Palancar Caves, lasted 93 minutes
  with a max depth of 89 fsw). Three days we were the only passengers. On the
  last, tired, I asked Jeremy to pick us up at 10:30 instead of 8-ish. That
  timing worked great, as the divers from the other boats were on their surface
  intervals when we got to our first site.
 My first visit to Cozumel was in the mid-70s, and even back then, I considered
  it a diving cliché. Returning in 2005, I was amazed at how well the
  reefs have held up, how good the diving is, the terrific atmosphere, and
  the comparatively low prices. It won't be another 30 years before I return.
 P.S.: Aldora Divers will soon have boats and equipment at the Hotel
  Ventanas al Mar on the unexplored east side of the Island. Here are walls
  with numerous sharks and old Spanish wrecks, where the occasional cannon and
  even doubloons are still found. This will not be easy diving and conditions
  may cause postponements, but it offers unique underwater adventure. For reservations,
  e-mail info@cozumelwindward.com.
 — D.L.
  Diver's Compass: Living Underwater can be reached at 011 52
  987 869 1813, or e-mail jeremy@living-underwater.com… Some
  restaurants and other businesses (e.g., Living Underwater and
  Omar Gomez' Fathom Diver Expeditions) don't take credit cards.
  Other places, such as the Dive Paradise, impose purchase minimums;
  take travelers checks or use the ATMs surrounding San
  Miguel's main plaza… Living Underwater charges $80 for a twotank
  dive and passes along a $2/day Marine Park fee. Nitrox
  is $10/ tank, and a 1-tank night dive is $45… There's shore diving from
  the Hotel Cozumel & Resort's beach, but the bottom looked pretty barren…
  Our seven-night stay at the Hotel cost $656… La Choza and Café Denis serve
  authentic (“típical”) Yucatecan cuisine; $35 for two, including drinks…
Diver's Compass: Living Underwater can be reached at 011 52
  987 869 1813, or e-mail jeremy@living-underwater.com… Some
  restaurants and other businesses (e.g., Living Underwater and
  Omar Gomez' Fathom Diver Expeditions) don't take credit cards.
  Other places, such as the Dive Paradise, impose purchase minimums;
  take travelers checks or use the ATMs surrounding San
  Miguel's main plaza… Living Underwater charges $80 for a twotank
  dive and passes along a $2/day Marine Park fee. Nitrox
  is $10/ tank, and a 1-tank night dive is $45… There's shore diving from
  the Hotel Cozumel & Resort's beach, but the bottom looked pretty barren…
  Our seven-night stay at the Hotel cost $656… La Choza and Café Denis serve
  authentic (“típical”) Yucatecan cuisine; $35 for two, including drinks…