Farmed Fish

Aquaculture spans an enormous range of species and systems, from extensive pond polyculture integrated with crop or livestock farming, to intensive cage culture in open water, to highly controlled recirculating systems. The choice of species and system depends on water availability and quality, climate, capital investment, and target markets.

Pond culture

Earthen or lined ponds, often used for species such as tilapia and carp, sometimes integrated with crop or livestock production.

Cage and pen culture

Net enclosures in lakes, rivers, or coastal waters, used for species including salmon and some tilapia and carp production.

Recirculating aquaculture systems (RAS)

Land-based tanks that filter and reuse water, allowing production with reduced water use and greater environmental control regardless of local climate.

Species and system choice is tied closely to local water resources, climate, and infrastructure; there is no single standard aquaculture system used worldwide.

Farmed fish are fed formulated diets, natural pond productivity (plankton and other organisms), or a combination, depending on species and system. Herbivorous and omnivorous species such as tilapia and carp can make substantial use of plant-based feed ingredients and natural pond food webs, while carnivorous species such as salmon require higher levels of protein and fish oil or alternative concentrated ingredients. Regardless of feed type, maintaining adequate dissolved oxygen, appropriate temperature, and low levels of ammonia and other wastes is essential to fish health and growth.

Fish health and welfare depend on water quality, stocking density, biosecurity to limit the introduction and spread of pathogens, and appropriate handling during grading, transport, and harvest.

Aquaculture has grown rapidly as a source of animal protein and now supplies a large share of the fish consumed globally, alongside wild capture fisheries. Integrated systems that combine fish culture with crop or livestock production, such as rice–fish farming, can make efficient use of land, water, and nutrients, while feed sourcing, effluent management, and disease control remain key considerations that vary by system and region.