Nothobranchius kafuensis – Kafue Killlifish
Wildekamp and Rosenstock first described Nothobranchius kafuensis in 1989. This species belongs to the family Nothobranchiidae. The genus name “Nothobranchius” comes from the Greek “not hos” (false) and “branchia” (gill), referring to the presence of “false” gills. The species name can be divided into two parts. -ensis is a conjugation indicating a place: the Kafue River system in Zambia, where the type locality of this species was collected.
There are no known synonyms for this species.
Description
Appearance:
Nothobranchius kafuensis has a stocky and high-backed body shape. Males are more colorful with an orange-red head and scales, while females have a more grayish-blue color. The fins of males are often bluish with red accents. The maximum length is about 6 centimeters for males, while females remain slightly smaller.
Differences between the sexes:
Males are more colorful and have longer fins than females. Behaviorally, males are more aggressive, especially toward other males.
Behavior and temperament:
These fish are generally peaceful, but males can be aggressive towards each other. They often live in pairs or small groups and are bottom dwellers.
Life expectancy:
In the wild, they live 6-10 months, but in an aquarium, they can live up to 2 years.
Biotope
Nothobranchius kafuensis is native to Zambia, particularly the Kafue and upper Zambezi rivers. They live in temporary pools and swamps that are seasonal. The habitat often has little submerged vegetation and a peat substrate. They live in a tropical climate with seasonal flooding.
Diet
In the wild:
They feed on worms and insect larvae.
In the aquarium:
Live food such as Artemia nauplii and tiny insect larvae are recommended. Avoid dry food as this does not mimic their natural diet.
The Aquarium
An aquarium of at least 60 centimeters is suitable for this species. A larger aquarium is needed for multiple pairs. The aquarium should have fine plants and root wood for hiding places. Use a peat substrate. The ideal water values are 25-28 ° C and pH 6.5-7.5. They can live well together with other peaceful species of similar size.
Breeding aquarium and conditioning
A special breeding tank is recommended, with a layer of peat as substrate. Condition the fish with live food and temporarily separate the males and females for breeding.
The Spawn
During spawning, the fish’s colors become more intense. The eggs are laid in peat and also stored in peat. The peat should then be stored in a plastic bag for 3 to 5 months.
Storing the eggs
To properly store Nothobranchius kafuensis eggs, follow these detailed steps:
- Dryness of Peat: Make sure the peat is dry enough. This is achieved when the outer edges of the peat turn brown and it no longer sticks to your hands.
- Plastic Bag Storage: Use a newspaper as a funnel to transfer the peat into a thick plastic bag. Avoid ziplock bags as these can allow moisture to escape.
- Condensation and Moisture Retention: Shake the bag to break up the peat lumps and roll it up like a pancake. This helps keep the moisture close to the peat. Use tape to keep the bag rolled up.
- Labeling: Write the species name, date of collection, and expected hatching date on the bag. Do not use a marker directly on the plastic to prevent the ink from damaging the eggs.
- Store in a Styrofoam Box: Place the bag in a Styrofoam box in a dark and cool place. This helps to keep the temperature constant.
- Regular Check: Open the bag every two weeks to check the peat. If there is a lot of condensation, dry the peat again. If it is too dry, add a piece of wet paper to retain moisture.
- Oxygen supply: Opening the bag occasionally and turning the peat will provide oxygen, essential for the eggs’ development.
By following these steps, you will ensure that your Nothobranchius kafuensis eggs have the best chance of hatching successfully.
Raising the fry
Hatching the Eggs
To determine if the eggs are ready to hatch, see if the eyes are visible through the eggshell. If you think the eggs are fully developed, you can wet the peat even if the eyes are not visible.
Setting up the hatching tank
Fill a plastic container with aged water to a depth of about 5 centimeters. Place the peat with the eggs in the container and carefully break the peat pieces. Carefully remove the floating debris once the peat has sunk to the bottom.
What to Do with Unhatched Eggs
If the eggs do not hatch immediately, dry and store the peat again. After two weeks, you can re-wet the peat, because some eggs need several wet periods to hatch, a process called diapause.
Food for the Young Fish
Once the fry hatch, they begin to swim rapidly. Start feeding infusoria, as this is suitable for the very smallest fry. As they grow, you can switch to microworms and then to Artemia nauplii.
Water Change and Survival
It is important to change water regularly to keep the water quality high. Change about 10-20% of the water weekly. Ensure there are not too many fry in one tank to keep the mortality rate low.
Particularities
Nothobranchius kafuensis is susceptible to diseases such as Ich, and a little salt in the water can help. However, due to their specific requirements, they are not suitable for beginners.
Conclusion
Nothobranchius kafuensis is a colorful and interesting species for experienced aquarists. It requires specific water conditions and feeding and is not suitable for beginners. Its short lifespan and specific breeding requirements make it challenging but also rewarding for the dedicated hobbyist.
Video
Author
John de Lange
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