Farnsworth Bank
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.
Farnsworth Bank rises from deep water off Catalina's rugged backside, its pinnacle tops paved with California's most celebrated marine growth: purple hydrocoral, a slow-growing species so distinctive the site received early protective designation on its account. The color reads even in the blue-green light at 25 m - branching violet thickets patrolled by sheephead, blacksmith clouds, and torpedo rays over the surrounding sand. Being an offshore high spot, the bank collects wanderers: sea lions commuting from the island, yellowtail, mola mola rising to be cleaned in the warm months. Swell and current guard it; boats cancel often, which keeps the hydrocoral unbroken and the dive a privilege.
The moment you come for: Purple hydrocoral gardens, open-water pelagic chances, Catalina's wild weather side
Topography: Volcanic pinnacles rising from deep water, crowned with purple hydrocoral
Current: An open-water bank off Catalina's weather side; trips run only in cooperative seas.
Know before you splash
Hazards: Exposure, surge at depth, current over the pinnacles; cold thermoclines.
Conservation: The hydrocoral is protected and brittle - buoyancy discipline is the entry fee; anchoring practices are restricted.
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
California Sea Lion
Mola Mola (Ocean Sunfish)
Nudibranchs
For photographers
Wide angle: ★★★★☆ · Macro: ★★★☆☆ — editors' 1–5 rating of what this site gives each style of shooting