Common carp

Water parameters

Minimum tank: 1000 L per individual at harvest size.

Feed and growth

Feed protein

28% target

Daily feed (warm)

1.80% of body weight

Daily feed (cool)

0.60% of body weight

Max density

50 g per litre

A 8000 g adult eats about 144.0 g of feed per day at optimum. 10 fish at adult size: ~1440 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

Cyprinus carpio is native to eastern and central Asia and eastern Europe, west to the Danube basin, with the wild form centered on the Caspian, Aral, and Black Sea drainages. It is one of the most cultured freshwater fish in the world, around four million tonnes a year, and among the first fish humans ever farmed, raised in China for over two thousand years and in Europe for several hundred. It lives in slow rivers, lakes, and ponds over muddy bottoms in warm water. The ornamental koi is a domesticated carp, now usually traced to the closely related Amur carp; goldfish, despite a common mix-up, are a separate species, Carassius auratus, not descended from common carp. Wild-type fish are deep-bodied, bronze to olive, and fully scaled, while domesticated forms include the mirror carp, with a few large scattered scales, and the leather carp, with almost none. The species handles an unusually wide range of conditions, from near-freezing water up into the mid 30s Celsius, very low oxygen for short spells, some salinity, and pH from about 6 to 9. That toughness, with fast growth and easy breeding, made it both the oldest farmed fish and, where introduced, a damaging invader. Big fish reach 70 cm and several kilograms, with exceptional individuals far larger, and the species can live past forty years.

Climate and outdoor ponds

Climate

temperate (handles seasonal swings)

USDA zones

3–12 (winter low around -40°C or warmer)

Heating needed

no

Cooling needed

no

Care notes

A workable aquaponics fish where carp is valued as food, across Central and Eastern Europe and much of Asia, or where other species are restricted. In the United States, Australia, and many tropical countries it is a notorious invasive, and stocking is regulated or banned, so check local rules carefully. Where it is allowed, carp is about the easiest aquaponics fish there is: it eats almost anything, from commercial pellet and grain to aquatic plants and kitchen scraps, puts up with poor water, reaches a harvest size of 500–1 g in twelve to eighteen warm months, and is rarely troubled by disease under decent conditions. Feed conversion on pellet runs about 1.5 to 2.0, and the fish takes crowding better than most, so stocking can be high. The real catch for Western growers is the market: carp is not popular table fare in North America or Australia, so raising a fish few will eat misses the point, whereas in Eastern European, Middle Eastern, and Asian kitchens it is prized. Feed any commercial fish pellet of 28 to 32 percent protein or a grain-based ration.

Further reading

• Fish for aquaponics: tilapia vs everything else