As a rule, Celestial Pearl Danios are not typically known to be fin-nippers. However, exceptions may occur, especially in overpopulated environments or where food is scarce. Providing your little swimmers with appropriate tank size, good nutrition, and aquatic conditions can ensure their peaceful demeanor remains intact.
Any changes in behavior or sudden traces of aggressive behavior should call for immediate attention. In situations like this, separating the nipping fish from the others or implementing specific behavioral interventions may be needed to maintain an overall peaceful aquarium environment.