THE NEON TETRA

       These fish live in shoals in the smaller rivers of South America. The tropical forest is like a green roof over the river. The leaves are so thick that they do not let the sun's rays through,

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and the water is black. The fish are used to living in darkness, and find each other with the help of the bright blue stripe on their bodies.
       If a shaft of sunlight gets through, it lights up the water and the stripe flashes like a neon advertisement on a city street at night. That is why this fish is called the Neon Tetra.