Melanotaenia splendida are normally found close to the surface of the deeper pools in small freshwater streams, they also occur in lakes and reservoirs. These fishes are frequently recorded in large schools and these can be found in water varying from clear to turbid and which may or may not have extensive vegetation.
M. splendida is an omnivore which feeds on filamentous algae, aquatic and terrestrial insects, small crustaceans and other small invertebrates. Like other rainbowfish, this species shows
sexual dimorphism. Breeding takes place year round and the male and female fish form pairs in which the females releases the eggs and the male fertilises them. 60-70 eggs are laid at each
spawning and the golden coloured, round eggs attach to submerged vegetation with an adhesive filament. The larvae hatch after around a week and are around 4mm long and they have a reduced yolk sac and fully formed mouth and
pectoral fins. The larvae start to feed after 24 hours. ==References==