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No federal permit to keepNeon tetra
Paracheirodon innesi
Fishes › Tetras, piranhas and pacus (Characiformes) › Characidae (Tetras)
The neon tetra (Paracheirodon innesi) is a species of freshwater fish belonging to the family Acestrorhamphidae, the American characins, of the order Characiformes.
Care at a glance
Species-specific values
Values researched for this exact species. Where they differ from the group guide below, follow these. Air, surface and water temperatures are listed separately, and each source is kept as published rather than averaged.
| Water temperature | 70–77 °F (21–25 °C) Maintenance recommendations from this source; do not replace with a multisource average. | 248 |
| Water pH | 4.0–7.5 Maintenance recommendations from this source; do not replace with a multisource average. | 248 |
| Water general hardness | 1–12 dGH Maintenance recommendations from this source; do not replace with a multisource average. | 248 |
| Adult standard length | 30 mm Maximum standard length reported by source; excludes caudal fin, not total body length. | 248 |
| Minimum tank base | length: 60 cm; width: 30 cm Minimum aquarium base recommended by this source, not a tank-volume specification. | 248 |
| Minimum social group | 8–10 fish Source recommends a group of at least 8–10; larger groups preferred. | 248 |
| Diet | Small prepared foods supplemented with small live or frozen invertebrates. | 248 |
Species-specific aquarium care
- Tank: At least 24 in long and 12 in front to back for one adult (adults commonly reach about 0.9 in / 2.22 cm).
- Water: Freshwater.
- Temperature: 68–79°F (range recorded for this species).
- pH: 5–7.
- Hardness: 1–2 dGH.
- Layout: An open-water swimmer: needs long, open swimming space with few obstacles.
- 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 24 × 12 in (roughly 14 US gallons); space needed is rated “modest tank”.
- Water: a fairly wide range, from slightly acidic to slightly alkaline, 70–77 °F, pH 4–7.5, 1–12 dGH.
- Behaviour: temperament peaceful; a shoaling fish best kept in a group of six or more; suited to a community tank.
- Difficulty: Easy (Seriously Fish rating).
Short excerpts from the species profile:
- Setup: “Provided healthy stock can be obtained (see 'Notes') maintenance presents few problems although it perhaps looks best in an arrangement comprising a sandy substrate plus some driftwood roots and branches.”
- Diet: “Likely to be omnivorous feeding on small invertebrates, crustacea, filamentous algae, fallen fruit and suchlike in nature.”
- Tankmates: “Generally peaceful making it an ideal resident of the well-researched community aquarium.”
- Breeding: “You'll need to set up a dedicated tank if you want to raise decent numbers of fry.”
From the Seriously Fish profile for this species, which has the full habitat, maintenance, diet, behaviour and breeding write-up 167
Tetras
Applies to most species in this group. Habitat: The covered characids include South American river and tributary fishes, from vegetation-shaded bloodfin habitats to sandy flowing rivers occupied by Exodon. [fg156-bloodfin, fg156-exodon]. Individual species can differ, so compare with the species numbers above and the linked sources.
Housing & setup
- For glass bloodfins, use at least 60 × 38 × 30 cm (24 × 15 × 12 in), retaining open upper-water swimming space.
- Provide planted margins and floating vegetation for bloodfins; fit a tight lid for Aphyocharax anisitsi.
- For bucktooth tetras use at least 120 × 45 × 45 cm (48 × 18 × 18 in), efficient filtration and planted refuges from bullying.
- For glass bloodfins maintain pH 6.0–7.5; for Exodon, pH 5.5–7.5.
Climate & lighting
| Water | 73.4–80.6°F |
Diet
- Small dried foods for glass and ordinary bloodfins.
- Daphnia, Cyclops and bloodworms for glass bloodfins.
- For Exodon, chopped prawns, mussels, earthworms and fish rather than live feeder fish.
Social life
- Glass bloodfins need 6–8 or more; ordinary bloodfins at least six. Exodon requires a species aquarium and at least 12 introduced together; small groups can kill one another.
Health watch
- Freshwater ich (white spot disease), a general aquarium risk.
- Bacterial infections associated with stress and poor water quality.
- Fin and scale damage from aggression, especially Exodon.
Understanding the animal
About this animal
About this animal
The type species of its genus, it is native to blackwater and clearwater streams in the Amazon basin of South America. Its bright colouring makes the fish visible to conspecifics in the dark blackwater streams, and is also the main reason for its popularity among freshwater fish hobbyists, with neon tetras being one of the most widely kept tropical fish in the world.
Quoted from the Wikipedia article “Neon 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. Feeds on worms, small insects, crustaceans and plant matter. In tank, female lays a relatively small number of eggs, which hatch in about 24 hours. |
| Water it lives in | Freshwater, 68–79 °F (20–26 °C), pH 5–7, hardness 1–2 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, 68–79 °F.
Native climate (measured)
Native climate (measured)
| Warm-season highs | about 90°F (up to 96°F in the hottest sampled areas) |
| Cool-season lows | about 70°F (down to 68°F in the coldest sampled areas) |
| Average temperature | 79–82°F across sampled records |
| Relative humidity | 80–84% on average (driest month about 80%) |
| Rainfall | about 2594 mm a year |
Measured at 33 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 neon tetra (Paracheirodon innesi) is a species of freshwater fish belonging to the family Acestrorhamphidae, the American characins, of the order Characiformes. The type species of its genus, it is native to blackwater and clearwater streams in the Amazon basin of South America. Its bright colouring makes the fish visible to conspecifics in the dark blackwater streams, and is also the main reason for its popularity among freshwater fish hobbyists, with neon tetras being one of the most widely kept tropical fish in the world. — 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 | The male is slender, and the blue line is straighter. The female is rounder, producing a bent blue line. Some aquarists say the females look plumper when viewed from above. — Wikipedia (community-edited) |
| Appearance and size | The neon tetra has a light-blue back over a silver-white abdomen. The fish is characterized by a bright iridescent blue horizontal stripe along each side of the fish from its nose to the base of the adipose fin, and an iridescent red stripe that begins at the middle of the body and extends posteriorly to the base of the caudal fin. The fish is partially transparent (including fins) except for these markings. — Wikipedia (community-edited) |
| Biology | Migratory behaviour is undetermined. Adults feed on worms, small insects, crustaceans and plant matter. In tank, female lays a relatively small number of eggs, which hatch in about 24 hours. — FishBase |
Data and studies
Researched care notes
Researched care notes
Findings checked against veterinary, zoo, welfare, keeper and peer-reviewed sources. Air, basking-surface and water temperatures are kept separate, and where sources disagree both are shown. “Study” notes report what a paper measured, not a universal rule.
Neon Tetra
- For Paracheirodon innesi, Seriously Fish gives a water-temperature range of 21–25°C; this is not a cardinal-tetra temperature recommendation.1
- Seriously Fish recommends an aquarium footprint of at least 60 × 30 cm; treat this as keeper guidance, not an experimentally validated minimum.1
- Keep a shoal; the species profile recommends at least 8–10 neon tetras rather than one or two.1
- Provide cover and subdued lighting, using suitable low-light or floating plants.1
- Offer appropriately small varied foods, including suitable dried foods and small frozen or live invertebrates.1
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 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.
Minimum tank footprint
Seriously Fish recommends a tank base of at least 24 × 12 in (about 14 US gallons).
Veterinary & husbandry research
Veterinary & husbandry research
- Pleistophora hyphessobryconis (Microsporidia) infecting zebrafish Danio rerio in research facilities Sanders JL et al., Diseases of aquatic organisms 2010
- Preliminary Investigations into Use of Metomidate for Euthanasia of Ornamental Fishes Yanong RPE et al., Journal of aquatic animal health 2021
- Cutaneous Ossifying Fibroma in a Neon Tetra (Paracheirodon innesi) Murphy B et al., Journal of comparative pathology 2016
- Temperature tolerance and oxygen consumption of two South American tetras, Paracheirodon innessi and Hyphessobrycon herbertaxelrodi Cooper CJ et al., Journal of thermal biology 2019
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. See all 7 on PubMed → 170
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: Prionobrama filigera Experienced keeper or breederAdded in the 2026 source-checked care-guide review.
- Seriously Fish: Exodon paradoxus Experienced keeper or breederAdded in the 2026 source-checked care-guide review.
- Seriously Fish: Aphyocharax anisitsi 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.
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