Simply by looking at it and comparing it with others of the same species.
Don't know tell me
a neon tetra is a fish. It has all sorts of neon colours on its body!
Green neon tetra was created in 1963.
Black neon tetra was created in 1961.
A neon tetra breaths the same way as any other fish with gills
A baby neon.
the scientific name for the Black neon tetra fish is Hyphessobrycon herbertaxelrodi
The female may develop a swollen belly, caused by the developing eggs.
it is slightly wider, and has a more curved blue stripe
Sounds like bloat.
i wouldnt recommend it as neon tetras should be kept in schools of 5 and the stress couldnt easily kill the tetra
Peru and Brazil.