Adult fish can grow to 20 centimetres (7. 9 in) in length, and 1–2 centimetres (0. 39–0. 79 in) in thickness. Adult males tend to be larger than females. Yellow tang are bright yellow in color. At night, the yellow coloring fades slightly, and a prominent brownish patch develops in the middle with a horizontal white band. They rapidly resume their bright yellow color during daylight. It's important to be aware, however, that Yellow Tang can be aggressive, are prone to the fish disease called "ich," and may damage coral your reef tank. Male and female yellow tang look very similar. When mating, however, males change color and have a "shimmering" behavior which makes them identifiable.
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