Mrigal

Quick facts

Adult size

80 cm, 8000 g typical harvest weight

Days to harvest

365 to 540 days from fingerling

Lifespan (max)

up to 12 years

Diet

omnivore

Temperature class

warm-water

Difficulty

beginner

Water parameters

Temperature range

14–32°C (optimum 26°C)

pH

6.5 to 8.5

Hardness

5 to 25 dGH

Minimum tank

2000 L per individual at harvest size

Feed and growth

Feed protein

28% target

Daily feed (warm water)

1.80% of body weight per day

Daily feed (cool water)

0.60% of body weight per day

Max stocking density

40 g per litre of system water

A 8000g adult eats about 144.0 g of feed per day at optimum temperature. For a roster of 10 fish at adult size, that's around 1440 g of feed daily.

Legality

Aquaculture and possession rules vary by jurisdiction and change over time. This table reflects regulations as of the verified date on each row. Verify with your local fisheries or wildlife authority before stocking.

Jurisdictions not listed here default to "check local regulations". A non-listing is not a green light; rules in your specific county or municipality may apply.

Habitat and origin

Native to rivers and floodplain lakes of the Indian subcontinent: India, Bangladesh, Nepal, Pakistan, and Myanmar. The species (Cirrhinus mrigala, sometimes listed as C. cirrhosus) is one of the three major Indian carps, along with catla and rohu. Mrigal is a bottom-feeder that consumes decayed organic matter, algae, and detritus from the substrate surface. In the traditional Indian carp polyculture system, mrigal occupies the bottom-feeding niche while catla feeds at the surface and rohu in the midwater column. Adults reach 1 m and up to 12 kg in the wild; culture harvest size is typically 0.5–2 kg at 12-18 months. India produces millions of tonnes of Indian major carps annually, with mrigal comprising a substantial portion. The flesh is white, soft, and bony, consumed widely across South Asia.

Climate and outdoor ponds

Climate classification

tropical (needs warm water year-round)

Outdoor pond zones (USDA)

9 to 13 (winter low around -7°C or warmer)

Heating in a temperate climate

Not required (handles seasonal cool periods)

Cooling in a temperate climate

Not required

Zone bounds reflect year-round outdoor pond viability with no active heating. Anywhere outside the bounded zone, the species can still be kept in an indoor heated tank or a seasonally-managed system. Verify your specific microclimate, as a sheltered yard zone can run a half-zone warmer than the regional rating.

Care notes

A warm-water bottom-feeding species for polyculture aquaponics, primarily relevant in South Asian contexts where the three-species Indian carp polyculture is the standard production method. Temperature range: 18–35°C, optimal at 25–32°C. Growth in polyculture ponds: 0.5–1.5 kg in 12-18 months. On commercial carp pellet (25-32% protein), FCR is 1.5-2.5. As a bottom-feeder, mrigal consumes detritus, uneaten feed, and benthic organisms that settle on the tank or pond floor, complementing surface-feeding catla and midwater-feeding rohu in a three-tier polyculture that maximizes total system productivity. Stocking in polyculture: 20-30% mrigal (bottom), 40-50% rohu (midwater), 20-30% catla (surface). In monoculture, stocking density is 10-20 g/L. Mrigal tolerate moderate water quality variations but prefer well-oxygenated water (DO above 4 mg/L) compared to the more tolerant common carp. They're hardy and disease-resistant under normal conditions. Fingerlings are abundantly available from government hatcheries and private breeders across India and Bangladesh at very low cost. The species is not commonly cultured outside the Indian subcontinent, partly because the soft, bony flesh doesn't match Western market preferences for boneless fillets. For South Asian aquaponics operations, mrigal fills an essential bottom-feeding ecological niche in polyculture and is a culturally accepted, affordable food fish with strong domestic market demand.

Further reading

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