Variable depth cage enclosing fish - has tubular framework with air tight upper part and lower part in communication with water

摘要

The aquaculture cage is made of a set of hollow tubes (2) defining the edges and six cupro-nickel grilles (4) defining the faces. The tubes comprising the lower edges of the cage have holes punched in them so that the interiors communicate with the water in which the cage is immersed. The upper tubes of the cage define a water-tight enclosure and this is connected to a flexible pipe (7). The upper end of the pipe is connected to a buoy which indicates where the cage is located. The air in the upper tubes keeps the cage upright.