Nippo Maru
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 Nippo Maru is the lagoon's cabinet of curiosities, a freighter that went down loaded for garrison resupply. A light tank still perches on the deck, gun barrels and howitzer carriages lie nearby, and the holds carry water tanks, shells, and crates that have fused into single rusted masses. The bridge is the famous frame: helm and engine telegraph standing in open water, instruments legible under the growth. Everything interesting sits below 30 m, so this is a dive of choices made quickly and gas watched closely — the wreck teaches discipline as surely as history.
The moment you come for: The deck tank; the standing bridge telegraph and helm; artillery pieces and garrison cargo in the holds.
Topography: Hull with a list to port on lagoon floor at roughly 48 m
Entry: Descend the mooring to the bridge and plan the dive around limited bottom time.
Know before you splash
Hazards: Depth is the governing hazard; narcosis at working depth; munitions in the holds; short no-deco windows invite overstay.
Conservation: Protected historic site; the artifacts photographed today exist because previous divers left them — extend the same courtesy.
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
Giant Moray Eel
Grey Reef Shark
Lionfish
Nudibranchs
For photographers
Wide angle: ★★★★☆ · Macro: ★★★☆☆ — editors' 1–5 rating of what this site gives each style of shooting