Murray cod

Quick facts

Adult size

70 cm, 2500 g typical harvest weight

Days to harvest

540 to 1095 days from fingerling

Lifespan (max)

up to 50 years

Diet

carnivore

Temperature class

warm-water

Difficulty

intermediate

Water parameters

Temperature range

8–27°C (optimum 22°C)

pH

6.5 to 8.5

Hardness

5 to 25 dGH

Minimum tank

1000 L per individual at harvest size

Feed and growth

Feed protein

45% target

Daily feed (warm water)

1.20% of body weight per day

Daily feed (cool water)

0.60% of body weight per day

Max stocking density

30 g per litre of system water

A 2500g adult eats about 30.0 g of feed per day at optimum temperature. For a roster of 10 fish at adult size, that's around 300 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 the Murray-Darling River basin in southeastern Australia. The species (Maccullochella peelii) is Australia's largest exclusively freshwater fish, reaching 1.8 m and over 100 kg historically, though specimens over 20 kg are now rare in the wild due to decades of overfishing, habitat degradation, and river regulation. Murray cod inhabit deep pools, undercut banks, and log jams in large, slow-moving rivers. The flesh is white, firm, moist, and exceptionally well-flavored, widely regarded as the best-eating native freshwater fish in Australia. Wild populations are listed as vulnerable and protected in most jurisdictions, but aquaculture of Murray cod is an established and growing industry.

Climate and outdoor ponds

Climate classification

temperate (handles seasonal swings)

Outdoor pond zones (USDA)

6 to 10 (winter low around -23°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 premium warm-water aquaponics species for Australian operators willing to manage a slow-growing but exceptionally high-value fish. Optimal temperature is 20–26°C, with a tolerated range of 4–30°C. The broad thermal tolerance is a practical advantage over barramundi (which dies below 15°C) and means Murray cod survive Australian winters in most mainland locations without supplemental heating. Growth is slow by aquaculture standards: 500–1 g in 18-24 months, reaching 2–5 kg in 3-5 years. FCR on high-protein pellet (45-50% protein) is 1.3-1.8, which is efficient for a predatory species. Stocking density should be low to moderate (8-15 g/L) because Murray cod are territorial ambush predators that become aggressive and cannibalistic at higher densities. Strict size-grading is essential: fish differing by more than 30% in body length must be separated, because larger individuals will eat smaller ones. The slow growth rate is compensated by exceptional flesh quality and strong market demand: Murray cod commands $25-50/kg in Australian restaurants and retailers, making it one of the highest-value freshwater species available. Fingerlings are available from specialized hatcheries across southeastern Australia, primarily in New South Wales and Victoria. Legal to culture in most eastern Australian states, though some jurisdictions require aquaculture permits. Water quality: DO above 5 mg/L, ammonia below 1 mg/L, pH 6.5-8.0. Murray cod is best suited for experienced aquaponics operators running larger systems who can commit to a multi-year production cycle.

Further reading

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