Contrary to their feminine name, Celestial Pearl Danios can exhibit a degree of territorial behavior, especially during the breeding period. They aren’t typically aggressive towards other species but display occasional male-to-male aggression triggered by competition during breeding.
This behavior, intriguingly termed as ‘pseudo-aggression’, involves elaborate tail displays, chasing, and non-harming nipping with seldom damage to the opponent. Managing this requires optimal tank size and suitable hiding spots complemented by maintaining a proper male-to-female ratio. This way, the occasional hostility from these otherwise peaceful fishes will be minimal and well-contained.