The green neon tetra (Paracheirodon simulans) is a freshwater fish of the family Characidae of order Characiformes.

It is native to the upper Orinoco and Negro Rivers in South America.

[2] This fish is similar in appearance to the closely related and better-known neon tetra, but it is slightly smaller, and its red patch is less pronounced, while the blue-green areas of the upper body are more brilliant.

The green neon tetra comes from extremely soft, acidic water at temperatures around 24 to 29 °C (75 to 84 °F).

Ideally, the water should be highly stained by the tannins from peat,[3] in subdued light, shaded by plants.