Species profile
Redtail Notho
Nothobranchius guentheri
Semi aggressive
Hard care
45 L minimum aquarium
4.5–6 cm adult size
Top mid
Minimum group: 3
About this species
General notes for hobby use.
Warm temperatures accelerate an already short annual life cycle. The lower end of the suitable temperature range is preferable for long-term maintenance if the fish remain active and healthy.
Water parameters
Suggested general range for long-term care.
Temperature
20–24 °C
pH
6–7.5
GH
2–12 dGH
KH
Not yet documented
Flow preference
Low
Data confidence
Verified
Behaviour
General behaviour traits used by TanksConnected compatibility checks.
Minimum group size
Minimum group: 3
Tank zone
Top mid
Territory level
Moderate
Predation risk
Tiny fry
Bioload factor
0.55
Males can be strongly competitive. A one-male/two-or-more-female arrangement with visual cover is safer than multiple males in a small tank.
Compatibility flags
Quick cautions for common tank-planning issues.
Fin nipper
No
Plant safe
Yes
Shrimp safe
No / caution
Snail safe
Yes
Cave breeder
No
Digs substrate
Yes
Jump risk
Yes
Natural history & care
Research-backed context for long-term aquarium care.
Lifespan
1–2 years
Diet type
Carnivore
Minimum aquarium volume
45 L
Minimum footprint
45 × 30 cm
Accepted scientific name
Nothobranchius guentheri
Alternative names
Redtail Notho, Günther's Killifish, Redfin Notho
Native range
Tanzania, including Zanzibar.
Natural habitat
Annual fish from temporary seasonal pools. Captive tanks should be calm, covered and planted, with soft substrate/spawning peat or an equivalent controlled spawning medium.
Diet & feeding
Small predatory insectivore. Live/frozen foods such as Artemia, daphnia, bloodworm and mosquito larvae are particularly useful; high-quality prepared foods may also be accepted.
Breeding & sexing
Research-backed guidance for identifying sexes and reproductive behaviour.
Sexing
Males are much more strongly coloured with red/orange caudal fins; females are smaller and relatively plain.
Breeding
Annual substrate spawner. Eggs are buried in the substrate and undergo a dry diapause before hatching when seasonal conditions return; breeding requires deliberate egg collection/incubation technique.