The global aquaculture production of crustaceans, shellfish and fish has to increase to satisfy
the growing demand and also to compensate for the reduced capture from overexploited
fisheries. Extending the area of brackish and fresh water ponds is constrained by the limited
availability of land and fresh water. Oxygen availability limits productivity of non-aerated
ponds to about 3500 kg/ha/year. In aquaculture ponds,