Water circulation apparatus and method

An apparatus for conditioning water in open fish breeding cages, the apparatus comprising:

• a tube immersed in water,
• a lower mouth located on its lower end and an upper mouth located on its upper end;
• means for adjusting the depth of said lower mouth;
• an impeller with its driver motor, coupled inside of the tube, able to draw major flows in both directions;
• an upper mouth configuration which directs said major flow vertically or in other directions able to create an upward major flow, when the impeller is drawing water upwardly, that dissolves and carries away, from the open fish breeding cages, an upper mass of contaminated water, because of uninterrupted outward currents, generated for said major upward flow, in all radial directions, once it reaches said upper mass of contaminated water;
• and
• wide range depth adjusting means for said upper mouth, which permits varying the thickness of the carried upper mass of contaminated water, when the impeller is drawing water upwardly, and drawing water from the surface, when the impeller is drawing water downwardly.