What do you mean by “cod”? That's the common name for many different fish species, including some freshwater species. Most people consider fish within the genera Gadus, the family Gadidae, and the order Gadiformes to be cods. read more
There is only one gadiform fish that is freshwater (spends its entire life in freshwater), all others are saltwater (spend their entire lives in saltwater). There are other unrelated species of fish whose common names are cod, such as eastern cod, black cod, and trout cod. Some of these are freshwater and some of these are saltwater. read more
Many cod live throughout most of the UK waters, although are generally seen as a winter fish in the south. They are found in the Northern Atlantic Ocean. Areas with the greatest amount of cod fishing include Newfoundland, Labrador, New England, Novia Scotia, Iceland, Alaska, Florida, The Mediterranean Sea, Indian Ocean, and The Gulf of Valdez. read more
The eastern freshwater cod (Maccullochella ikei), also known as the eastern cod or Clarence River cod, is a large predatory freshwater fish of the genus Maccullochella and the family Percichthyidae, that occur in the coastal Clarence River system of north-eastern New South Wales. read more