Lake Kutubu Rainbowfish
Melanotaenia lacustris
A slow-developing rainbowfish whose true colors take patience to unlock.
About
The Lake Kutubu rainbowfish (Melanotaenia lacustris) comes from one of the most geographically restricted natural habitats of any aquarium fish. A single highland lake and its outlet river in the Southern Highlands of Papua New Guinea. That origin matters both ecologically and practically: the species is listed as vulnerable by the IUCN, and wild populations have faced pressure from overfishing and industrial development near the lake. If you pick some up, be aware that juveniles sold in stores look nothing like the blue-bodied adults in photos, and full coloration can take well over a year to develop even with excellent feeding. The wait is worth it. Males develop vivid coloration and an orange flush near the gill area, and they show it off most readily when kept with other members of their own species. A group of six or more is the way to go. This is a schooling fish that becomes noticeably more confident and colorful in numbers. It is peaceful toward tankmates but active enough that smaller, slower fish may find its energy level stressful. Good companions include danios, barbs, characins, and similarly sized rainbowfish. The species appreciates a well-planted tank with some cover, plenty of open water for swimming, and a reasonably sized footprint to accommodate a proper group.
Similar species
Other fish you might consider
Good tank mates
Species that tend to coexist peacefully with Lake Kutubu Rainbowfish
From the same region
Share the same natural habitat. Great for a biotope-themed tank
Frequently asked questions
- How big does the Lake Kutubu Rainbowfish get?
- The Lake Kutubu Rainbowfish reaches about 2.5–5" as an adult.
- What size tank does the Lake Kutubu Rainbowfish need?
- A minimum of 29 gallons is recommended for the Lake Kutubu Rainbowfish, with more room needed for a proper group.
- What water parameters does the Lake Kutubu Rainbowfish need?
- The Lake Kutubu Rainbowfish does best with a temperature of 72–82°F, a pH of 6.5–8.5, hardness around 8–25 dGH.
- Is the Lake Kutubu Rainbowfish aggressive?
- The Lake Kutubu Rainbowfish is generally peaceful and suits a community tank with similarly calm tankmates.
- What does the Lake Kutubu Rainbowfish eat?
- The Lake Kutubu Rainbowfish is an omnivore. It does well on a varied diet of quality flake or pellet plus occasional frozen or live foods.
- How long does the Lake Kutubu Rainbowfish live?
- With good care, the Lake Kutubu Rainbowfish typically lives 5-8 years.