Neon does not react with water. It doesn't react with anything.
Guppies will eat neons tetra babies but are not large enough to eat fully grown neons.
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.
no it is a gas
it is a cucumber
no.
Not for long. The neons would be eaten pretty quickly.
That engine is only in the Neons.That engine is only in the Neons.
it is nonmetal
it smell's bad
Generally no. Depending on the local police department, they MAY permit neons.
faulty water pump, electric fan, or a clogged radiator> With dodge motors it is usually a clogged radiator. Drain it
Neons feed mainly on small water creatures like Daphnia, and insect larvae like Mosquito larva.