What Types of Sea Fish Are There? A Guide to Common Sea Fish Species

Sea fish is a general term for fish that live in the ocean. They have adapted to salty seawater environments and are found from shallow coastal waters to the vast deep sea. In everyday usage, sea fish mostly refers to marine commercial fish that can be used as food, and the variety is extremely rich.

Divided by the water layer they inhabit, sea fish can be broadly classified into pelagic fish and bottom-dwelling fish. Pelagic fish such as sardines, mackerel and tuna have strong swimming ability and often move in schools; bottom-dwelling fish such as turbot and flounder have flat bodies and are accustomed to lying close to the seafloor. Yellow croaker, hairtail and others mostly live in coastal waters or deeper layers, and they are likewise common species on the dining table.

Sea fish generally have tender or firm flesh and are rich in high-quality protein and unsaturated fatty acids, making them a good source of protein in a balanced diet. However, it should be noted that large fish at the top of the food chain are more likely to accumulate heavy metals in their bodies, so their consumption frequency and portion size should be controlled; there is no need to pursue only expensive or rare varieties.

When choosing sea fish, you can check whether the eyes are clear and bright, whether the gills are bright red, and whether the flesh springs back after being pressed. Fresh chilled sea fish should smell of a faint salty fishiness similar to seawater, not a pungent off-odor. In addition, turbot and yellow croaker are often mistaken for freshwater fish, but they are in fact both sea fish; although sardines live in relatively deep waters, by habitat layer they still belong to pelagic fish and are not deep-sea fish in the strict sense.