Saltwater fish

Saltwater fish, also called marine fish or sea fish, are fish that live in seawater. Saltwater fish can swim and live alone or in a large group called a school.
Saltwater fish are very commonly kept in aquariums for entertainment. Many saltwater fish are also caught to be eaten, or grown in aquaculture. However, many fish species have been overfished and are otherwise threatened by marine pollution or ecological changes caused by climate change.
Habitat.
Saltwater fish live in the ocean. For example, the butterfly kingfish lives in the ocean. This ray-finned fish has had many common names, including big-scaled mackerel, bigscale mackerel, common gasterochisma, gasterochisma, butterfly mackerel, butterfly tuna, pachycormid, little pachycormid, scaled tunny, scaly tuna, and others.
Threats.
Saltwater fish face many threats. Common threats include overfishing, pollution, habitat loss, destruction, climate change, and invasive species. These threats come with a multitude of negative direct and indirect affects to marine ecosystems.