Coho salmon
Oncorhynchus kisutch
Also known asSilvers · Hooknose
Water parameters
Minimum tank: 2000 L per individual at harvest size.
Feed and growth
- Feed protein
- 45% target
- Daily feed (warm)
- 1.20% of body weight
- Daily feed (cool)
- 0.70% of body weight
- Max density
- 40 g per litre
A 4500 g adult eats about 54.0 g of feed per day at optimum. 10 fish at adult size: ~540 g daily.
Legality
Rules vary by jurisdiction and change over time. Verify with your local fisheries or wildlife authority before stocking.
| Jurisdiction | Status | Notes |
|---|---|---|
| us-general | check local regulations | Pacific salmon stocking is regulated by individual states; most require permits for non-native introductions verified 2026-05-14 |
Unlisted jurisdictions default to "check local regulations".
Origin and habitat
Oncorhynchus kisutch, the coho or silver salmon, ranges along both sides of the North Pacific, from Hokkaido and eastern Russia around the Bering Sea to Alaska and south to Monterey Bay in California. It is anadromous: the young rear in streams for about a year or two, drop to the ocean to feed and grow, and return after one to three years at sea to spawn. The name silver comes from the bright metallic sheen of ocean-phase fish. Coho are mid-sized among Pacific salmon, adults usually 3 to 6 kg and 60 to 76 cm. The flesh is orange-red, moderately fatty, firm, and well flavored, rated second only to chinook among the Pacific salmon. Wild runs have dropped in many rivers, and several Pacific Northwest population groups are listed as threatened or endangered under the US Endangered Species Act. Farming is concentrated in Chile, which produces the large majority of the world's farmed coho, around 200,000 tonnes a year out of a global total near a quarter million tonnes, with most of it exported to Japan; Japan itself farms a smaller amount.
Climate and outdoor ponds
- Climate
- cold-water (cool water required, dies in heat)
- USDA zones
- 3–7 (winter low around -40°C or warmer)
- Heating needed
- no
- Cooling needed
- yes, if summer water exceeds upper tolerance
Care notes
A cold-water salmon with limited use in freshwater aquaponics, here for reference. Coho need cold water around 8–14°C and high dissolved oxygen, comfortably above 7 mg/L, since salmonids struggle below about 6. The freshwater parr-to-smolt phase runs twelve to eighteen months and yields a fish of only 10–30 g before the animal is driven to migrate; growing coho to market size, 2–4 kg, entirely in fresh water is done in some Chilean and Japanese recirculating systems but takes careful management. Feed conversion is about 1.2 to 1.5 on a salmon pellet of 40 to 48 percent protein, and RAS stocking runs 30 to 50 g/L with added oxygen. For practical freshwater aquaponics, rainbow trout or arctic char are easier, since they complete their whole lives in fresh water without fighting a migratory drive. Coho fingerlings come from some Pacific Northwest hatcheries, but conservation rules restrict their sale in many areas, and legal status depends on whether stock is wild-derived or domesticated and varies by state and province. The usual salmon diseases apply: bacterial kidney disease, vibriosis, and IHN virus. Not a sensible home-aquaponics choice.