Topic summary
Blue-water diving

Extracted from the Wikipedia article Open-water diving.
Blue-water diving
Blue-water diving is done in mid-water where the bottom is out of sight of the diver and there may be no fixed visual reference. It is done by scientific divers for direct observation and sampling of pelagic organisms and particulate matter, particularly the gelatinous zoo-plankton that are fragile and transparent, making them relatively inaccessible by other methods, and by recreational divers for observation and photography of a range of organisms not easily seen in inshore waters.