The Neon Tetra boasts a shiny blue stripe that runs from the tip of its head to the adipose fin - a small rounded fin located above the tail. The iridescent quality of this blue stripe helps to reflect light, and it's believed to enhance the fish's visibility among other tetras.

Just below the blue stripe lies a partial red streak that begins in the middle of the fish's body and extends all the way to the tail. This red streak can often lead to confusion with the Cardinal Tetra, which bears a similar but longer stripe. While the Neon Tetra's stripe only crosses half of its body, the Cardinal Tetra's stripe spans its entire length.

The fish's underbelly is a neutral white color, while its body is generally translucent, enabling it to blend into its natural surroundings and evade predatory fish.