Product Details

Pagwi Rainbowfish – Melanotaenia affinis “Pagwi”

The Pagwi Rainbowfish is a lively New Guinea rainbowfish with attractive metallic colour, active shoaling behaviour and strong male display. Correctly listed as Melanotaenia affinis “Pagwi”, this locality form is associated with the Sepik River region of Papua New Guinea and should be kept as a distinct line where breeding is intended. It is peaceful with suitable tank mates, but it is an energetic fish that needs a spacious, mature aquarium with clean water and open swimming room.

Key Identification:

Common Name: Pagwi Rainbowfish
Other Names: New Guinea Rainbowfish, North New Guinea Rainbowfish, Pagwi New Guinea Rainbowfish
Scientific Name: Melanotaenia affinis “Pagwi”
Fish Type: Rainbowfish / Melanotaeniid
Water Type: Freshwater

Natural Range & Habitat:

Melanotaenia affinis is native to northern New Guinea, with the Pagwi form associated with the Sepik River region of Papua New Guinea. Pagwi is an important locality name in the hobby and should be treated separately from other M. affinis forms if maintaining a breeding line.

In the wild, New Guinea Rainbowfish inhabit freshwater rivers, streams, backwaters and vegetated margins. In the aquarium, Pagwi Rainbowfish should be kept in a mature, well-filtered setup with open swimming space, planted edges, moderate flow and good oxygenation.

Appearance & Adult Size:

Pagwi Rainbowfish have the streamlined, laterally compressed body shape typical of active rainbowfish. Colour varies with sex, age, mood and lighting, but settled males may show blue-green, silver, yellow, bronze, red or coppery tones, with attractive fin colour and display flashes. Females are usually smaller, slimmer and more subtly coloured.

Adults usually reach around 9–11 cm, making this a medium-sized rainbowfish that needs more room than small tetras or nano species. The best colour is usually seen in mature males kept in a settled mixed-sex group.

Aquarium Suitability:

This species is best suited to larger peaceful community aquariums, planted rainbowfish displays and active New Guinea-style setups. It needs open midwater swimming lanes, plants around the sides and back, clean water and enough space for males to display.

Pagwi Rainbowfish are not suitable for tiny aquariums, shy nano communities, aggressive cichlid tanks, predator aquariums or cramped layouts with little swimming room. They are peaceful, but their constant movement can intimidate small or nervous fish.

Recommended Aquarium Size:

A practical minimum is 180 litres for a group, with a tank length of at least 100 cm recommended. Larger aquariums of 240 litres or more are preferred for mature groups, mixed rainbowfish displays and stronger long-term colour development.

Keep in a group of at least 6, with 8 or more preferred. A mixed-sex group is ideal, as males show stronger colour and display behaviour when females and rival males are present.

Water Conditions:

Temperature: 24–28°C
pH: 6.5–7.8
Hardness: Soft to moderately hard
Additional Notes: Keep water clean, stable and well oxygenated. This species is adaptable when captive-bred, but it should not be exposed to sudden water-chemistry swings, poor oxygenation or high nitrate. Regular partial water changes and strong biological filtration are recommended.

Temperament & Tank Mates:

Aquarium Category: Community Fish

Pagwi Rainbowfish are peaceful but active community fish. Suitable tank mates include other rainbowfish of similar size, larger peaceful tetras, danios, robust rasboras, peaceful barbs, Cory-type catfish in compatible temperatures, bristlenose plecs and other confident community species.

Avoid very small nano fish, shy slow feeders, delicate long-finned species, large predators and aggressive cichlids. Adult rainbowfish may eat very small fry or tiny shrimp, so they are not ideal for shrimp-breeding aquariums.

Feeding:

Pagwi Rainbowfish are easy-feeding omnivores. Offer quality flakes, small floating or slow-sinking granules and rainbowfish pellets as the staple diet. Supplement with frozen or live foods such as daphnia, cyclops, brineshrimp, mosquito larvae, bloodworm and small insect-based foods.

A varied diet helps support colour, body condition and display behaviour. Feed small amounts that are eaten quickly, as active rainbowfish have strong appetites and do best with clean water.

Behaviour in the Aquarium:

This is an active midwater swimmer that spends much of the day moving through open areas of the aquarium. Males may display to females and rival males by intensifying colour, flaring fins and making short chasing movements. This is normal in a suitable group and usually does not cause harm when enough space is provided.

Pagwi Rainbowfish are egg scatterers. Females deposit adhesive eggs among fine plants, mosses or spawning mops, and adults do not provide parental care. Fry require separate rearing if breeding is intended.

Care Notes:

Add Pagwi Rainbowfish only to a mature, fully cycled aquarium. Provide open swimming room, stable water quality and a secure lid, as active rainbowfish can jump when startled. Avoid overcrowding, poor oxygenation and long periods without water changes.

Do not mix Pagwi fish with other Melanotaenia affinis locality strains if breeding for line purity. Keeping locality forms separate helps preserve clear, traceable aquarium lines and prevents accidental mixing between strains.

Recommended For:

Intermediate

Availability:

Occasional / Specialist rainbowfish strain, usually captive-bred when available

Image Disclaimer:

All images are a visual representation of the fish you will receive, made to be as accurate as possible. Natural variation in size, body colour, metallic sheen, fin colour, sex, age and markings can occur between individual fish.