Near Bowen, North Head Island at low tide.
3 inches long, on the inshore wall, about 1.5 feet down from the surface. Growing alone - single trunk/individual, not many separate trunks/individuals. Overall appearance was delicate, feather-like, flat, and black/dark blue & white. It swayed in the current from a fixed point at the bottom. Only that one seen during 1 hour snorkel. Seen by two people.
pink thing, center of frame. soft coral?