How to Identify Blue Tang Fish

Blue tangs are brightly-colored species of surgeon fish that occur in the Atlantic, Pacific and Indian Oceans and are sold for salt-water aquariums.

Instructions

1. 

   Look for schooling fish with dark blue, flat bodies, blue fins with horizontal dark navy blue stripes and down-turned mouths. These are adult Atlantic or Caribbean blue tangs. Only the caudal spines at the base of the tail are yellow in adult Atlantic blue tang fish.

2. 

   Check for vivid blue eyelids in juvenile Caribbean blue tangs, which are yellow with blue edges on fins and tail. Caribbean blue tangs gradually change to blue coloration when they reach three to five inches length, and grow to a maximum length of 15 inches.

3. 

   Snorkel or scuba dive in the western Pacific or eastern Indian ocean for the other two species of blue tang fish. Look for a yellow triangular tail patch on the regal blue tang, also called the 'Indo-Pacific blue tang'. They have a dark navy blue stripe and swirl along the dorsal part of the body, and grow up to 12 inches long.

4. 

   Look for stripes and patches of yellow, white and dark navy blue on the very colorful powder blue tang, also from the western Pacific and eastern Indian ocean region. The powder blue tang has a dark blue face, a yellow stripe along the base of the dorsal fin, and can grow up to 21 inches long.

Tips & Warnings

• If you’re thinking of keeping blue tangs at home, all three species of blue tang fish require an aquarium of at least 75 gallons capacity.