How are freshwater fish different from saltwater fish?

Saltwater fish are found in various habitats, ranging from the cold Antarctic and Arctic oceans to warmer tropical seas. Habitats that best suit saltwater fish include coral reefs, salt ponds, mangroves, seagrass beds and the deep sea, and a range of fish have developed to thrive in each of these conditions. read more

Freshwater fish can be cold-water fish or tropical fish. Cold-water fish are mainly goldfish, while tropical fish that can live in warmer water include many varieties. Examples of tropical freshwater fish include angelfish, discus, cichilds, barbs and Cory cats. read more

The difference between saltwater and freshwater fish is that saltwater fish need to prevent hyponatremia and freshwater fish need to prevent dehydration. This is because water tends to move from a place that has a lesser concentration of salt to one that has a greater concentration of salt. read more