All fish / Melanotaeniidae

Papuan rainbowfish

Melanotaenia papuae

Also known as papuan rainbow, papua rainbowfish, papuae rainbowfish, melanotaenia papuae, メラノタエニア・パプアエ, ikan pelangi papua, 巴布亚彩虹鱼

This is a small, active rainbowfish with a silvery blue body, a dark lateral stripe and fins edged in red or orange, and males colour up strongly when displaying. It stays fairly compact and is hardy, so it suits planted community tanks where a lively shoal can show off.

Care at a glance

Care level

Easy

Temperament

Peaceful

Adult size

6 cm

Temperature

24 to 29 °C

pH

6.5 to 8

Smallest tank

110 litres

Keep as

Shoal of 6 or more, ideally with more females than males

Diet

Omnivore: quality flakes and small pellets, frozen bloodworm, brine shrimp and daphnia, plus some vegetable matter

Swims

Middle of the tank

Lifespan

4 to 6 years

Water

Freshwater

Wild range

Southeastern Papua New Guinea (streams near Port Moresby, Laloki and Brown River area)

Breeding

It scatters adhesive eggs over fine-leaved plants or spawning mops over several days, and the eggs hatch in about a week. Breeding is easy, and the fry need infusoria or other very fine foods at first.

Good to know

Keep it apart from other Melanotaenia species to avoid hybrids, as wild-type lines are valued by hobbyists. It is a fast swimmer and may nip or stress very slow, long-finned tankmates.