Atlantic salmon

Quick facts

Adult size

75 cm, 5000 g typical harvest weight

Days to harvest

540 to 1095 days from fingerling

Lifespan (max)

up to 13 years

Diet

carnivore

Temperature class

cold-water

Difficulty

advanced

Water parameters

Temperature range

2–20°C (optimum 14°C)

pH

6.5 to 8

Hardness

3 to 20 dGH

Minimum tank

2000 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)

0.80% of body weight per day

Max stocking density

60 g per litre of system water

A 5000g adult eats about 60.0 g of feed per day at optimum temperature. For a roster of 10 fish at adult size, that's around 600 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 draining into the North Atlantic Ocean, from Portugal and Spain to Norway and Iceland in Europe and from Connecticut to Labrador in North America. The species (Salmo salar) is anadromous in the wild: fish spawn in freshwater rivers, juveniles spend 1-3 years in fresh water as parr, then undergo smoltification and migrate to the ocean, returning to their natal river to spawn after 1-3 years at sea. Atlantic salmon is the most commercially important salmonid in the world, with global production exceeding 3 million tonnes annually from marine net-pen farms, primarily in Norway, Chile, Scotland, Canada, and Tasmania. The freshwater phase of production (smolt rearing) and the rapidly growing sector of full-cycle land-based recirculating aquaculture systems (RAS) make Atlantic salmon relevant to freshwater culture and, at commercial scale, to integrated aquaponics-style production.

Climate and outdoor ponds

Climate classification

cold-water (cool water required, dies in heat)

Outdoor pond zones (USDA)

3 to 7 (winter low around -40°C or warmer)

Heating in a temperate climate

Not required (handles seasonal cool periods)

Cooling in a temperate climate

Required if your summer water temperatures exceed the upper tolerance

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

Not a typical home aquaponics species due to the complexity and scale required, but included because land-based Atlantic salmon RAS facilities represent a fast-growing aquaculture sector and several commercial operations are exploring integration of plant production with salmon waste streams. The species requires cold water (8–14°C for optimal growth), high dissolved oxygen (above 7 mg/L), and pristine water quality (ammonia below 0.5 mg/L, CO2 below 15 mg/L). Growth in freshwater RAS is moderate: smolts reach 80–150 g in 12-18 months, and post-smolts can be grown to 3–5 kg harvest size entirely in freshwater at 12–14°C over 24-36 months. FCR is excellent at 1.1-1.3 on high-quality salmon pellet (40-48% protein, 20-30% fat). Stocking density in well-managed RAS: 40-80 g/L with supplemental oxygen. Disease management is demanding: ISA, BKD, sea lice (marine), and Saprolegnia require biosecurity protocols. Smolts are available from commercial hatcheries but in quantities suited to large operations. The economics require volume. For home aquaponics, rainbow trout or arctic char are far more practical cold-water alternatives.

Further reading

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