Tangs are beautiful marine coral reef fish with extraordinarily vibrant colors making them popular among collectors. They are protective of their territory and travel together most times in what are called schools.
The Tang is a very colorful fish, its variety of color is very wide and each is eye-catching in its own way. Some different species each with its own coloring are the; Purple Tang, Sailfin Tang, Scopas Tang, and the Yellow Tang which are under the Genus Zebrasoma.
They all have a forward facing spine on each side of the causal peduncle, which is the horizontal stripe on the base of the tail. This spine has angular edges that result in a scalpel like sharpness along its length. Adult Tangs range from 6-15 inches in length and most can grow very quickly. 
Tangs' normal look is an intense, uniform color as if showing emotion through colors. Emotions such as stress, fighting, and "becoming barred" can manipulate the colors to a point that they appear blanched, usually with red, eroded, or blotchy markings on their body.
Tangs reproduce by spawning in pairs or schools. Spawning being the production or depositing of eggs in large numbers with two or more Tangs swimming rapidly toward the surface releasing their gametes. You can find the difference between male or female Tangs by their show of color or structural differences when compared and contrasted.
Some of them live in the Indian Ocean as well as some in the waters of the French Polynesian Islands. You can find them in the Red Sea and European waters as well.  They can be found in every tropical ocean and many tropical seas but the Atlantic Ocean does not suffice as its year round temperatures are too cold for them.
Tangs are herbivores and eat algae and will eat with great appetite continuing to do so for as long as there is a supply available for them. Tangs will eat brine shrimp actually causing them to develop a sunken belly very fast and subsequently causing death. Most if not all Tangs would eat all the time if they could. They get very sensitive and very protective over their territory and will fight with their same species or other Tangs seriously damaging them. Usually the same Tangs with the same colors get into more fights to protect their territory, but as a group the Tangs are the least dangerous. 
Tangs are more susceptible to disease than most fish because they get easily stressed which can cause a parasitic outbreak. Yellow Tangs can be diagnosed with the "black spot" disease as well. Scientists have found that Vitamin C is an excellent way to cure and prevent any disease for the Tangs, especially for Black Spot, Fin Rot, and degradation of the skin. 
- The Sailfin Tangs, Surgeons, Doctorfishes, of the Genus Zebrasoma
- Zebrasoma Tangs and Reef Aquariums
- Tang (Fish)