A swarm of four-foot reef sharks swam in circles very near to us, but were not threatening. Scariest thing on that dive was the ten-meter citron (lemon) shark propelling rapidly just above the ocean floor. All the other sharks got out of its way.
We also swam near an indigenous giant Napoleon wrasse.
In shallower water around Bora we swam next to a group (a radiance?) of slow-moving Manta rays; very graceful.
On Hawaii, Big Island Divers will take you on a black-water dive at night. The boat goes out a mile offshore, beyond the edge of the Mauna Kea volcano, where the ocean floor is 7,000 feet deep. The divers jump in the water, tethered to the boat with sturdy lines. The divemasters on board shine a strobe light into the water. You just hang there weightlessly for 45 minutes, watching very strange pelagic creatures swimming close by, many of them digesting each other. Thrilling!
OMG that night dive sounds like shark bait.