There are 80 known species of tang, that inhabit the tropical waters of the southern hemisphere, including the largest species of the tang group, the white margin unicorn fish that has been known to grow over a meter long.
Due to it's small size, the tang has many predators in it's shallow ocean environment including larger fish, eels, sharks, crustaceans and large invertebrates such as jellyfish. Tang are also preyed upon by human who mainly catch them to keep in artificial aquariums.
Tangs are known to breed all year round in the tropical regions, beginning with a male tang securing himself a temporary breeding territory that includes a pair or group of female tang. The female tang release an average of 40,000 eggs into the water which are then fertilised by the male tang. The baby tang are known as fry and hatch in less than a week. Tangs however are reported to breed as well when in captivity.
The tang is one of the most popular species of marine fish to be kept in tanks and aquariums around the world. People are charmed by the peaceful and gentle nature of the tang, along with it's bright colours and the fact that tangs can live for a long time (average is between 12 and 15 years), especially compared to other species of marine fish of a similar size.
Tang are not recommended to be kept in small aquariums as tang have the potential to get pretty big. The most common type of tang kept in salt-water aquariums are the yellow tang and the bright blue regal tang but despite the fact that the tang is popular fish to keep they need to be well looked after and have specific water conditions maintained.