Home / Fishes / Killifish and livebearers / Redtail notho
No federal permit to keepRedtail notho
Nothobranchius guentheri
Fishes › Killifish and livebearers (Cyprinodontiformes) › Nothobranchiidae (African killifish)
The redtail notho (Nothobranchius guentheri) is a species of killifish in the family Nothobranchiidae.
Care at a glance
Species-specific aquarium care
- Tank: At least 24 in long and 12 in front to back for one adult (adults commonly reach about 1.4 in / 3.5 cm).
- Water: Freshwater.
- Temperature: 72–77°F (range recorded for this species).
- pH: 6–7.
- Hardness: 4–10 dGH.
- Layout: Uses both the bottom and open water: give open swimming space plus cover near the substrate.
Calculated from this species' own FishBase record: tank size from its typical adult length and swimming zone, water values from its recorded ranges. The group guide below fills in general care.
Care guide
Species care notes
- Tank: a base of at least 18 × 12 in (roughly 11 US gallons); space needed is rated “modest tank”.
- Water: a fairly wide range, from slightly acidic to slightly alkaline, 72–77 °F, pH 6.5–8.
- Behaviour: temperament fights its own; in a pair; not a community fish.
- Difficulty: Moderate (Seriously Fish rating).
Short excerpts from the species profile:
- Setup: “Use a dark, soft substrate and give it dense planting, floating plants and some wood for cover, with subdued lighting.”
- Tankmates: “Best kept in a species tank.”
From the Seriously Fish profile for this species, which has the full habitat, maintenance, diet, behaviour and breeding write-up 167
African killifish
Applies to most species in this group. Habitat: African killifish occupy permanent small streams and swamps as well as seasonal floodplain pools that dry out, where annual Nothobranchius survive as eggs. Individual species can differ, so compare with the species numbers above and the linked sources.
Housing & setup
- For an Aphyosemion australe pair or trio, provide at least a 45 × 25 cm (18 × 10 in) footprint; a Nothobranchius rachovii pair needs at least 45 × 30 cm (18 × 12 in).
- Fit a tightly sealed cover: lyretails are accomplished jumpers.
- Provide floating vegetation to shade the water and plants or spawning mops; Epiplatys use surface vegetation for egg laying.
- Use gentle aeration or filtration; maintain clean water and separate breeding species and locality strains.
- Collect annual N. rachovii eggs in spawning medium for separate incubation; its profile specifies 5–7 months of storage before wetting.
Climate & lighting
| Water | 70–75°F |
Diet
- Live or frozen Daphnia and Artemia.
- Chopped bloodworms and appropriately sized worms.
- Small insects for surface-feeding Epiplatys; tiny live foods for small fry.
Social life
- A. australe can be kept as a pair or trio with carefully selected peaceful companions; breeding tanks should hold one species and locality strain.
Health watch
- Velvet susceptibility in A. australe fry.
- Fungal loss of incubating eggs.
- Nutritional deficiencies from an unsuitable diet.
Understanding the animal
About this animal
About this animal
It is endemic to Zanzibar. Its natural habitats are intermittent rivers and intermittent freshwater marshes.
Quoted from the Wikipedia article “Redtail notho” (CC BY-SA 4.0) 174
In the wild
In the wild
From this species’ own FishBase record (habitat, bottom type, water and breeding data), not its family. Good care copies these conditions.1
| Where it lives | Lives in freshwater, in rivers and streams, mangroves. Uses both the bottom and open water. Found in temporary pools, swamps, ditches and small streams. |
| Water it lives in | Freshwater, 72–77 °F (22–25 °C), pH 6–7, hardness 4–10 dH. |
| Climate | Tropical climate. |
| Behavior to plan for | Breeding: brood hiders. |
What this means for care
- Keep water within its wild range, 72–77 °F.
From the sources
From the sources
Quoted from the matching sections of reputable sources for this exact species. Specialist databases are used first; Wikipedia (community-edited, CC BY-SA 4.0) only fills gaps. Other sources are short credited quotes.
| Overview | The redtail notho (Nothobranchius guentheri) is a species of killifish in the family Nothobranchiidae. It is endemic to Zanzibar. Its natural habitats are intermittent rivers and intermittent freshwater marshes. The redtail notho eats mosquito larvae and other planktonic creatures. — Wikipedia (community-edited) |
| Where it lives | Home ranges Population dynamics Growth parameters Max. ages / sizes Length-weight rel. Length-frequencies Mass conversion Recruitment Abundance Life cycle Reproduction Maturity Maturity/Gills rel. — FishBase |
| Reproduction | Thrives in seasonal rainwater pools. Spawns throughout the short breeding period until the pool dries up and all fish die except their drought-resistant eggs. Eggs go through a dry period of many weeks. — FishBase |
| Biology | Found in temporary pools, swamps, ditches and small streams. Used for biological control of mosquitos. One of the so called 'annual fishes' which has eggs that can withstand seasonal droughts. — FishBase |
Data and studies
The numbers
The numbers
Each bar is what one source reports. Where several sources weigh in, the dashed gold band marks their average.
Maximum recorded lifespan
Longest recorded lifespan reported by each database; typical lifespans are usually shorter. The AnAge record comes from an animal in human care.
Adult length
Maximum recorded length. Measured as standard length (snout to the base of the tail, not counting the tail fin). Fish in home aquariums often stay smaller than wild records.
Water temperature
Range the species tolerates in nature; aim for the middle.
Water hardness
Minimum tank footprint
Seriously Fish recommends a tank base of at least 18 × 12 in (about 11 US gallons).
Veterinary & husbandry research
Veterinary & husbandry research
- Reversible stage-specific embryonic inhibition mediated by the presence of adults in the annual fish Nothobranchius guentheri Inglima K et al., The Journal of experimental zoology 1981
- Male conspicuous coloration covaries with aggression but not with exploration in the short-lived annual fish Nothobranchius guentheri Demidova TB et al., Scientific reports 2026
Peer-reviewed papers that mention this species alongside captivity, zoos, veterinary care or aquaculture. Some cover several species or mention it only in passing, so check the abstract. 170
Sources for this sheet
- AnAge: The Animal Ageing and Longevity Database (Human Ageing Genomic Resources) Peer-reviewed researchCurated, referenced longevity and life-history records for thousands of species; maximum lifespans are often from zoo animals.
- FishBase (Froese & Pauly, eds.), version 24.07 Peer-reviewed researchThe global scientific database on fishes, maintained by a consortium of research institutions; every value is referenced.
- Seriously Fish species profiles Experienced keeper or breederLong-running aquarium reference written and peer-checked by experienced fishkeepers and ichthyologists; each profile covers habitat, tank size, water, diet, behaviour and breeding.
- Seriously Fish — aphyosemion australe Experienced keeper or breederAdded in the 2026 source-checked care-guide review.
- Seriously Fish — nothobranchius rachovii Experienced keeper or breederAdded in the 2026 source-checked care-guide review.
- American Killifish Association — The AKA Beginners Guide Experienced keeper or breederAdded in the 2026 source-checked care-guide review.
- Merck Veterinary Manual — Disorders and Diseases of Fish Zoo, university or veterinaryAdded in the 2026 source-checked care-guide review.
- Wikipedia (species article) Community referenceFree encyclopedia; useful overviews with their own citations. Intro text is quoted under CC BY-SA 4.0.
- PubMed (U.S. National Library of Medicine) Peer-reviewed researchIndex of peer-reviewed veterinary, zoo and husbandry research.
- iNaturalist (captive observations) Community referenceCommunity observation platform run by the California Academy of Sciences and National Geographic; observations marked captive show animals living in homes, zoos and aquariums.
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