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No federal permit to keepCongo tetra
Phenacogrammus interruptus
Fishes › Tetras, piranhas and pacus (Characiformes) › Alestidae (African tetras)
The Congo tetra (Phenacogrammus interruptus) is a species of fish in the African tetra family, found in the central Congo River Basin in Africa.
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 3.1 in / 8 cm).
- Water: Freshwater.
- Temperature: 73–79°F (range recorded for this species).
- pH: 6–8.
- Hardness: 5–19 dGH.
- Layout: Uses both the bottom and open water: give open swimming space plus cover near the substrate.
- Diet: Eats a varied diet: mix quality prepared foods with frozen and live foods. FishBase classes it as a omnivore.
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 47 × 12 in (roughly 29 US gallons); space needed is rated “large tank”.
- Water: a fairly wide range, from slightly acidic to slightly alkaline, 73–82 °F, pH 6–7.5, 3–18 dGH.
- Behaviour: temperament peaceful.
- Difficulty: Easy (Seriously Fish rating).
Short excerpts from the species profile:
- Setup: “Ideally an African biotope tank with driftwood branches, floating vegetation and anubias.”
- Diet: “An omnivore feeding on small worms, insects, crustaceans, algae and other zooplankton in nature.”
- Tankmates: “Peaceful but may scare shy species with its active swimming and large adult size.”
From the Seriously Fish profile for this species, which has the full habitat, maintenance, diet, behaviour and breeding write-up 167
African tetras
Applies to most species in this group. Habitat: African freshwater habitats range from the Congo drainage occupied by Congo tetras to large rivers and lakes inhabited by giant tigerfish. Individual species can differ, so compare with the species numbers above and the linked sources.
Housing & setup
- Adult Congo tetras need at least 120 × 30 × 30 cm (about 48 × 12 × 12 inches).
- For Congo tetras, combine plants, floating vegetation and driftwood with open swimming space and good circulation.
- Congo-tetra source parameters are pH 6.0–7.5 and hardness 3–18 dGH; maintain consistently high water quality.
- Hydrocynus goliath needs a facility-scale system: the source suggests roughly 15,000 litres rather than a home aquarium.
- For giant tigerfish, prioritize oxygenation, clean water and open swimming space with minimal hard decor.
Climate & lighting
| Water | 73.4–82.4°F |
Diet
- For Congo tetras: suitable dried omnivore foods including algae-based foods.
- For Congo tetras: small live or frozen worms, insects and crustaceans.
- For tigerfish: appropriately sized dead fish such as whitebait.
Social life
- Congo tetras suit mixed-sex shoals with peaceful companions; fin-nippers damage male fins. Adult giant tigerfish should be kept alone and may attack smaller fish without warning.
Handling
- Giant tigerfish require professional separation and maintenance procedures because adults pose a serious bite hazard.
Health watch
- Ammonia toxicity.
- Nutritional deficiencies.
Understanding the animal
About this animal
About this animal
It is commonly kept in aquaria.
Quoted from the Wikipedia article “Congo tetra” (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. Uses both the bottom and open water. Feeds on worms, small insects, crustaceans and plant matter. |
| Water it lives in | Freshwater, 73–79 °F (23–26 °C), pH 6–8, hardness 5–19 dH. |
| Climate | Tropical climate. |
| Behavior to plan for | Breeding: open water/substratum egg scatterers. |
What this means for care
- Keep water within its wild range, 73–79 °F.
Native climate (measured)
Native climate (measured)
| Warm-season highs | about 88°F (up to 89°F in the hottest sampled areas) |
| Cool-season lows | about 66°F (down to 64°F in the coldest sampled areas) |
| Average temperature | 76–78°F across sampled records |
| Relative humidity | 79–83% on average (driest month about 76%) |
| Rainfall | about 1686 mm a year |
Measured at 40 wild occurrence records sampled against WorldClim 2.1 climate data (1970–2000 averages). Air conditions in the range are ecological context, not enclosure settings: microhabitats such as burrows, leaf litter or basking rocks can be cooler, warmer or more humid.
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 Congo tetra (Phenacogrammus interruptus) is a species of fish in the African tetra family, found in the central Congo River Basin in Africa. It is commonly kept in aquaria. — 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 | In tank, after vigorous driving by the male, the female lays up to 300 eggs, sometimes more, which sink to the bottom. Eggs hatch after about 6 days. — FishBase |
| Appearance and size | The Congo tetra has a typical full-bodied tetra shape with rather large scales. When mature, the iridescent colors of the Congo tetra run through the fish from front to back, starting with blue on top changing to red through the middle, to yellow-gold, and back to blue just above the belly. — Wikipedia (community-edited) |
| Biology | Migratory behaviour is undetermined. Adults feed on worms, small insects, crustaceans and plant matter. Aquarium keeping: in groups of 5 or more individuals; minimum aquarium size 100 cm. — FishBase |
| Conservation | The IUCN lists the Congo tetra as a species of Least Concern. — Wikipedia (community-edited) |
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.
Adult length
Maximum recorded length. Measured as total length. Fish in home aquariums often stay smaller than wild records.
Water temperature
Range the species tolerates in nature; aim for the middle.
Minimum tank footprint
Seriously Fish recommends a tank base of at least 47 × 12 in (about 29 US gallons).
Sources for this sheet
- 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 — Phenacogrammus interruptus Experienced keeper or breederAdded in the 2026 source-checked care-guide review.
- Seriously Fish — Hydrocynus goliath 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.
- 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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