El Acuario (The Aquarium)
Depth is the range from the top of the site to its usual maximum; "recommended cert" is the mainstream-agency level operators usually ask for, not a legal rule. Currents and visibility change daily — treat everything here as planning ranges.
The Aquarium is where Malpelo shows off sheer biomass rather than any single species. Leather bass, grouper, and creole fish smother the terraces; jacks and snapper school so thickly over the boulders that the rock disappears and reappears with the current's pulse. Whitetips lie in ranks in every trench, morays thread between them, and the sanctuary's headline sharks - silkies and Galapagos sharks near the surface, hammerheads deeper - transit constantly because at Malpelo there is nowhere they do not transit. As the closest thing the island has to a gentle dive, it usually opens a trip, recalibrating what a diver considers a fishy site.
The moment you come for: Overwhelming fish density, whitetips stacked in trenches, sharks in constant transit
Topography: Boulder terraces and rock faces alive with encrusting growth
Current: Among the more sheltered corners of an unsheltered island; still expect flow and surge.
Know before you splash
Hazards: Surge near the rock, current at the exposed ends.
Conservation: Sanctuary rules apply; the no-take zone around Malpelo is among the largest in the eastern Pacific.
Nitrox: Worth it here — profiles sit in the range where enriched air meaningfully extends no-stop time (with the training to use it).
Who you'll meet
Galápagos Shark
Scalloped Hammerhead
Silky Shark
Whitetip Reef Shark
For photographers
Wide angle: ★★★★★ · Macro: ★★☆☆☆ — editors' 1–5 rating of what this site gives each style of shooting