Nothobranchius rungwaensis
Nothobranchius rungwaensis
The Rungwa annual killifish features vibrant blue and gold patterns, with distinguishing elongated fins and a slender body shape.
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About the Nothobranchius rungwaensis
A tiny annual killifish from seasonal pools in the Rungwa River system of western Tanzania, males glow blue-green with yellow-and-black fin bands. It grows fast, reaches maturity in a few weeks, and its eggs develop dry in peat, which is part of the fun for dedicated keepers.
Also known as
Quick Facts
Size
4.2 cm SL (male)
Temperament
Semi-aggressive
Difficulty
Intermediate
Min Tank Size
5 gallons
Lifespan
6-12 months
Origin
East Africa (Tanzania)
Diet
Carnivore - live and frozen foods (brine shrimp, daphnia, insect larvae; will take prepared foods less readily)
Water Parameters
23-24°C
Need a heater for this species?
This species needs 23-24°C in a 5 gallon tank. Use our heater calculator to find the right wattage.
Calculate heater sizeCare Notes
- Give them at least a 5-gallon tank and plan a species-only setup; with their semi-aggressive nature, a single male with females works better than multiple males in a small space.
- Hold the temperature steady at 23-24 C; this narrow range suits Nothobranchius rungwaensis.
- Use a tight-fitting lid; like many killifish, they jump.
- Feed a meaty diet of live and frozen brine shrimp, daphnia, and insect larvae; they take prepared foods less readily.
- Expect a short 6-12 month lifespan; they grow fast and reach maturity in just weeks, so line up breeding plans early.
- For breeding, offer a container of peat for spawning; collect the peat with eggs and let them develop dry, then re-wet to hatch.
- Males are the blue-green fish with yellow-and-black fin bands; use that to sex the group and limit male-male sparring in tight quarters.
Compatibility
Good Tankmates
- Best as a species-only setup: 1 male with 2-3 females, or a small group in a well-planted 10+ gallon with lots of cover and gentle flow
- Peaceful bottom-dwelling dwarf Corydoras (pygmaeus, habrosus, hastatus) in a group, on sand, in 10+ gallons
- Otocinclus catfish for algae control in established, well-oxygenated planted tanks
- Nerite and other hard-shelled snails that are too tough to be bothered
- Adult Amano shrimp, with dense plants and hides; expect juveniles to be eaten
- Kuhli loaches (Pangio spp.) in larger, quiet setups (20+ gallons) with sand and plenty of shelter
Avoid
- Fin-nippers or slow long-finned fish (barbs, serpae; bettas, fancy guppies) - nipping or being nipped
- Very active, fast mid-top swimmers that outcompete or stress them (danios, larger rainbowfish)
- Other surface-dwelling killifish species - fighting and hybridization risk
- Dwarf shrimp and other fry-sized invertebrates - will be hunted
Nothobranchius rungwaensis is a tiny annual killifish from seasonal pools in the Rungwa River system of western Tanzania. Males glow blue-green with bold yellow-and-black fin bands. It grows fast, reaches maturity in a few weeks, and lives 6-12 months. Expect semi-aggressive behavior, especially from males, and plan care around a cool 23-24 C and a diet of live and frozen foods.
Origin and natural habitat
This species is native to western Tanzania, where it occupies seasonal pools associated with the Rungwa River system. These temporary waters fill during the rains and then dry. N. rungwaensis is an annual killifish adapted to this cycle: the adults live quickly, spawn into the substrate, and the eggs endure the dry phase in the mud until the next wet season.
Aquarium setup and water conditions
A dedicated nano tank of at least 5 US gallons works for a small group. Keep flow gentle with a sponge filter or similarly calm filtration. Provide cover and broken lines of sight using plants or decor so subdominant fish can get out of view. Temperature should be held at 23-24 C.
Soft, fine substrate is useful if you intend to breed them, as they deposit eggs into the bottom. Many keepers offer a removable container of damp peat or fine fiber for this purpose. Lighting can be on the subdued side to help the fish feel secure and show their colors.
Killifish are adept jumpers. Use a tight-fitting lid with no gaps.
Diet and feeding
Carnivorous by nature, N. rungwaensis does best on live and frozen foods. Offer brine shrimp, daphnia, and insect larvae. Prepared foods are taken less readily, so do not rely on flakes or pellets. Vary the menu and feed small portions to match their size.
Behaviour and tankmates
This is a semi-aggressive, feisty little killifish. Males display and spar, and can be hard on each other in tight quarters. A species-only setup is the safer choice. If you keep more than one male, provide ample cover and visual breaks to reduce chasing.
Breeding
Breeding is well established in aquaria and is part of the appeal. As an annual killifish, N. rungwaensis is a substrate spawner whose eggs develop dry in peat. Offer a container of peat or similar fine medium; the fish will dive into it to lay. Remove the medium with eggs, squeeze to damp (not wet), and store sealed for the embryos to develop. After the development period, re-wet to trigger hatching. Fry are large enough to take small live foods such as newly hatched brine shrimp, and they grow quickly, reaching maturity in weeks.
Common problems and how to avoid them
- Short lifespan: plan ahead by raising a subsequent generation rather than waiting until the original group ages.
- Reluctance to accept dry foods: keep live and frozen options on hand; relying on prepared foods often leaves them underfed.
- Male aggression: reduce line-of-sight, keep to species-only tanks, and avoid crowding.
- Jumping: a tight cover is non-negotiable.
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