Pangasius

Water parameters

Minimum tank: 3000 L per individual at harvest size.

Feed and growth

Feed protein

28% target

Daily feed (warm)

2.50% of body weight

Daily feed (cool)

1.00% of body weight

Max density

80 g per litre

A 44000 g adult eats about 1100.0 g of feed per day at optimum. 10 fish at adult size: ~11000 g daily.

Legality

Rules vary by jurisdiction and change over time. Verify with your local fisheries or wildlife authority before stocking.

Unlisted jurisdictions default to "check local regulations".

Origin and habitat

Native to the lower Mekong, Chao Phraya and Maeklong river basins of mainland Southeast Asia, where it lives as a benthopelagic fish of large rivers. Wild populations are migratory, running upstream in the Mekong to spawn between roughly May and July, then dropping back to the main channel and seeking rearing habitat as water levels fall later in the year. Adults grow large: the maximum recorded size is about 1.3 m and 44 kg, though most big wild fish weigh closer to 30–40 kg. The species is farmed almost entirely in the Mekong Delta of Vietnam, which supplies the large majority of the world's pangasius, raised in deep earthen ponds and harvested at roughly 0.8–1.5 kg. Annual farmed output runs well over 1.5 million tonnes, sold mainly as frozen white fillets to the United States, the European Union and more than a hundred other markets. The flesh is pale, soft and mild. Trade names are inconsistent: 'swai' and 'tra' usually refer to this species, while 'basa' properly denotes a related pangasiid, Pangasius bocourti.

Climate and outdoor ponds

Climate

tropical (needs warm water year-round)

USDA zones

10–13 (winter low around -1°C or warmer)

Heating needed

yes

Cooling needed

no

Care notes

A warm-water river catfish suited to commercial tropical aquaculture rather than home systems. It tolerates poor water far better than most farmed fish because it breathes air: a modified swim bladder works as an accessory air-breathing organ, and under low oxygen or high carbon dioxide the fish shifts to aerial respiration and surface gulping. That trait is what lets Vietnamese growers hold extreme pond densities with heavy aeration and frequent water exchange, while aquaponics systems should stock far more conservatively, around {density:20}-{density:40}. Growth is fast on floating pellet feed of roughly 28 to 32 percent protein, with feed conversion near 1.5 to 1.8 under good management. The fish is strictly tropical and slows or stops growing in cool water, so temperate production needs heated water year round, and the energy cost makes small Western operations uncompetitive against imported frozen fillets. Adults are active and need horizontal swimming room, so long or round tanks suit them better than small square ones. Fingerlings come from catfish hatcheries across Vietnam, Thailand and Indonesia. Where warm water is naturally available, as in Southeast Asia, tropical Africa or Central America, pangasius is one of the highest-volume food-fish options.

Further reading

• Aquaponics water chemistry: balancing pH for fish and plants
• Fish for aquaponics: tilapia vs everything else