It sounds like some kind of abscess. If the fish is in the correct conditions for neons there's not much you can do. Neons need soft water, less than 4dGH, slightly acid pH6.5 to 6.8, fairly warm around 78F to 80F, zero nitrite and zero ammonia. If your conditions are not what are required for Neons (As above) you will have no success keeping neons or other (Amazonian) fish that require those conditions.
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
Question is not clear. Do you mean: "What types of tetra fish are there?" Neon, black neon, black, headlight-taillight, bleeding heart, carninal, glow-lite, to name a few, and there are many others.
It's sick and/or dying.
it is slightly wider, and has a more curved blue stripe
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.
About 4 species.