Lake Kutubu Rainbowfish (Melanotaenia lacustris)

Lake Kutubu Rainbowfish Melanotaenia lacustris
Name	Lake Kutubu Rainbowfish
Name Lat.	Melanotaenia lacustris
Family	Rainbowfishes
Family lat.	Melanotaeniidae
Order	Silversides
Order lat.	Atheriniformes
Origin	New Guinea
Habitat	Lake Kutubu
Diet	Omnivore
pH	7.6-8.1
Behavior	Peaceful
Keeping	Group
Care Level	Moderate
Reproduction	Egg scatterer
Breeding	Moderately difficult
Life Span	5-8 years
Protection	No
Metric Units
Size	10 cm
Temperature	20-25 °C
Hardness	10-20 °dH
Aquarium	200 l
US Units
Size	3.9"
Temperature	68-77 °F
Hardness	178-356 ppm
Aquarium	50 gal

Distribution and habitat

The distribution area of the Lake Kutubu rainbowfish is Lake Kutubu and its only outflow, the Soro River, in the southern highlands of Papua New Guinea. There they live mostly in schools, in still, crystal clear water with dense underwater vegetation, among roots and branches

Maintenance

The aquarium should have a dense background and edge planting, with hiding places (roots, stones) and plenty of free swimming space. A fine sandy substrate and clear, medium hard water is ideal

No ammonia, ammonium and nitrite should be detectable, the nitrate value should not exceed 100 mg/l. To ensure the water quality and oxygen content, a filter and heater adapted to the aquarium size is required, as well as lighting for the species-appropriate day-night rhythm of the animals.

Diet

The food supply consists of live food, such as cyclops, daphnia, mysis, artemia and mosquito larvae, which is also accepted without problems in frozen form, supplemented with commercially available frozen special food mixtures. They also need some vegetable food, such as algae leaves, pureed leafy and wild vegetables or dry food (flakes, granules, pellets) with vegetable components (spirulina, kelp)

It is recommended to feed small portions several times a day. A regular and varied diet promotes health and increases resistance. Only as much should be fed as is eaten immediately (in a maximum of 10 minutes).

Behaviour and compatibility

They are lively and swimming fish, which show their most beautiful coloration in the shoal. At least 5, but preferably much more Kutubu Rainbowfish should be kept together. In too small groups they are often quarrelsome. They can be socialized well with rainbowfish of similar size, but also with other fish. Basically, only compatible fish species with similar water condition and water temperature requirements should be socialized.

Sex dimorphism

The male is much more colorful than the slightly smaller female.

Reproduction and breeding

They are free spawners, which during the reproductive period daily in the morning (morning sun) deposit their eggs with adhesive filaments in fine-leaved plants. The fry hatch after 6-7 days. The parents do not engage in brood care.

Fry must be fed several times a day with special rearing food (dust food, infusoria). In community tanks breeding is hardly possible, because the spawn is easy prey.

Important

They like to jump, so the aquarium should be well covered.

The coloration of adult fish may vary somewhat, depending on the water quality.

The well-being of the fish should be checked regularly. Temperature should be checked daily, pH, hardness and nitrate levels should be checked at least every 14 days. Regular partial water changes are recommended, even if the contaminant level has not yet reached the upper limit. Sudden changes in water quality should be avoided. Newly introduced fish must be accustomed slowly to the water in the aquarium.

Further literature can be found in your pet store.

References

Text: Werner Winter; Image: Franz Lowak

Source: BMELV (1998): Tierschutzgutachten - Haltung von Zierfischen (Süßwasser); BAENSCH & RIEHL (2004): Aquarien Atlas Bd. 2, Mergus Verlag; ENGELMANN (2005): Zootierhaltung - Tiere in menschlicher Obhut: Fische, Verlag Harri Deutsch

• Gemäß § 21 Abs. 5 Tierschutzgesetz idgF