COMMERCIAL RECIRCULATING POND SYSTEMS IN LATIN AMERICA

Limitations on the availability of land, water or both, and the desire for increased control over the production environment have led some commercial producers of tilapia and shrimp in Latin America to develop recirculating pond systems.  The features of these systems will be reviewed.  One clear conclusion can be drawn:  the design of such systems is not based on rational principles or a clear understanding of pond ecology.  Nonetheless, these systems enable good crop production (10-15 t/ha) without widespread use of paddlewheel aeration.  It appears that water movement, even in hypereutrophic conditions, provides a sufficient supply of dissolved oxygen to cultured animals, including benthic-dwelling penaeid shrimp.  An approach that considers minimum mixing to overcome light limitation of algal growth is proposed.  Furthermore, internal mixing of ponds, as opposed to managing ponds as flow-through systems with recirculation to reservoirs, may be a more effective approach.