Rainbow fishes are colourful shoaling fish that originate from South East Asia to Australia, but are now all bred in asia. They are peaceful fast swimming fish that occupy the middle to surface of the aquarium.
Rainbow fish usually get more colourful as they mature, so a Red Rainbowfish will be duller as a juvenille.
Although these are peaceful I have known large rainbows to attack small amano shrimps, so ensure you only have larger shrimps or buy the shrimps when the rainbows are small.
Rainbows are not fussy with regards to pH, thriving in a large pH range from 6-7.5.
Feed them on a balanced diet of good quality flake food and frozen, shrimps, daphnia and bloodworms.