The system includes support structures (1) having first connection elements (10) for the uprights (7) which form part of the components (4 and 5) for carrying the rearing compartments (6), and second connection elements (14) on the flotation tubes (2) of a moveable platform. The elements (10) and the uprights (7) are provided with corresponding openings (11 and 13) to be actuated by removable connection devices (12) in order to permit the retaining or releasing of the uprights (7). A crossbar (16), provided with a means for coupling (17), keeps the components (4 and 5) joined together providing a module (18) which can be easily handled and can be separated from the support structure (1) with the rearing compartments (6).
