Once you've been towed out to the descent point just off Manuelita Island, you'll begin your descent at about 10m per minute. No need to equalize as you go down, just sit back and enjoy the ride - this is a DeepSee Submersible Cocos dive!
Once you near the ocean floor at 295ft (90m), you'll attain neutral buoyancy and then slowly move towards Everest over the sandy sea bed. The process of attaining buoyancy requires the use of compressed air. When excess air is jettisoned, it bursts towards the surface and this attracts mobula rays that swoop overhead, seeming to delight in the sensation of bubbles on their underbellies.
Usually daylight penetrates this deep, but sub-lights will lead the way to help you find some of the deep water benthic creatures such as the endemic redlipped Cocos batfish. The seamoth-type creature hops around on modified 'fin legs' and is unmistakable once you've spotted one. Other creatures you might see here include crabs, snake eels and flounders.
But don't focus too much attention on the sea floor as most of the spectacular sightings will be overhead. Small schools of skipjack tuna and scores of Hammerhead sharks will swim slowly above, perfectly silhouetted by the brighter sea surface.
Gradually, the volcanic mountain will loom up ahead. Visibility is pretty good this far down in the ocean, and the covering of basket stars and snow-like white octo corals on the lower slopes together with the mountain peak towering menacingly over 130ft (40m) above, is probably what gives this underwater mountain and Cocos dive site its name.
More deep water creatures can now be seen, such as deep water bigeyes, scythe butterflyfish, cabrilla groupers, and the rather odd looking brotula fish. Examination of the black coral bushes will yield scores of tiny gobies, anthias and moray eels.
Now as you look up you'll see thousands of creolefish swarming the peak with yellowfin tuna in hot pursuit. Giant marble rays drift effortlessly over the slopes in search of octopus, goliath grouper and Panama graysby lurk behind the slope ridges.
Then as you ascend back into normal recreational depths, familiar normalcy takes over again. Dense groups of schooling fish, such as mullet groupers and big eye trevally and Pacific crevalle jacks, are likely to engulf you as you begin to surface. This unique Cocos diving experience is one that will live with you for a very long time.
Everest Reef Basics: Submerged mountain
Depth: 148 - > 300ft (45 - >90m)
Visibility: 65 - 115ft (20 - 35m)
Surface conditions: Usually calm
Water temperature: 68 - 82°F (20 - 28°C)
Experience level: Once in a lifetime
Number of dive sites: 1
Diving season: All year round
Distance: 340 miles (550 km) from Costa Rica
Access: DeepSee Submersible only