Into the CanopyAnimal care sheets

Home / Fishes / Carp, barbs, minnows, loaches / Danionidae / Danionella priapus

No federal permit to keep

Danionella priapus

Danionella priapus

Fishes › Carp, barbs, minnows, loaches (Cypriniformes) › Danionidae (Danios and rasboras)

Danionella priapus is a species of Danionella endemic to India.

Aquarium hobby
Experience: Easy
Danionella priapus
Photo: Beta Mahatvaraj, CC BY-SA 4.0, via Wikimedia Commons
FamilyDanios and rasboras
Adult lengthup to 0.6 in
WaterFreshwater

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 0.6 in / 1.6 cm).
  • Water: Freshwater.
  • Layout: Uses both the bottom and open water: give open swimming space plus cover near the substrate.
  • Availability: Rarely or never seen in the aquarium trade; expect to source it from specialists or not at all.

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, 64–75 °F, pH 6–8, 1–8 dGH.
  • Behaviour: temperament species tank; a shoaling fish best kept in a group of six or more; not a community fish.
  • Difficulty: Moderate (Seriously Fish rating).

Short excerpts from the species profile:

  • Setup: “Should be maintained in a planted set-up with gentle water movement, ideally with a layer of vegetation covering at least part of the surface.”
  • Diet: “Quite easily-fed despite its delicate appearance.”
  • Tankmates: “Given its diminutive size and the fact that breeding should be a priority for anyone interested in keeping it this species is best kept alone.”
  • Breeding: “This species may not have been bred in aquaria although Pete Liptrot and Paul Dixon of the Bolton Museum Aquarium, UK, have achieved great success with an unidentified congener, probably D.”

From the Seriously Fish profile for this species, which has the full habitat, maintenance, diet, behaviour and breeding write-up 167

Group care guide

Danios and rasboras

Applies to most species in this group. Habitat: These Asian fishes occupy habitats ranging from zebra-danio pools and rice paddies to shaded harlequin streams, rocky Devario streams and planted galaxy-rasbora wetlands. [fg159-zebra, fg159-harlequin, fg159-giant, fg159-galaxy]. Individual species can differ, so compare with the species numbers above and the linked sources.

Level 2 reflects common aquarium species. Water range is ONLY for zebra danios; harlequins use 69.8–82.4°F, galaxy rasboras 68–78.8°F and D. aequipinnatus 60.8–78.8°F. [fg159-zebra, fg159-harlequin, fg159-galaxy, fg159-giant] Avoid routine tannin-rich wood/leaf additions for galaxy rasboras. [fg159-galaxy] Giant danios are often misidentified as D. aequipinnatus. [fg159-giant] Obtain separate profiles for the listed Rasbora and T. espei before using these examples as a stocking prescription.

Housing & setup

  • Use at least 90 × 30 cm (36 × 12 in) for zebra danios.
  • Harlequins require at least 60 × 30 cm (24 × 12 in), shaded planted cover and subdued light.
  • Devario aequipinnatus needs at least 120 × 45 cm (48 × 18 in), oxygenated water, moderate flow and a tight lid.
  • Galaxy rasboras need dense planting and broken sight lines in at least 45 × 30 cm (18 × 12 in), with gentle sponge filtration.
  • Match chemistry: harlequins pH 5.0–7.5, 1–12 dGH; galaxy rasboras pH 6.5–7.5, 5–15 dGH.

Sources 877878879880

Climate & lighting

Water64.4–77°F

Sources 877878879880

Diet

  • Quality flakes or granules sized to the fish.
  • Live or frozen Daphnia and Artemia.
  • Bloodworms for zebra danios, harlequins and Devario.
  • Small sinking foods for galaxy rasboras, which rarely feed at the surface.

Sources 877878879880

Social life

  • Keep zebra danios and harlequins in groups of at least 8–10. Galaxy males spar: dense cover and larger groups distribute aggression. Active Devario can overwhelm timid feeders.

Sources 877878879880

Health watch

  • Pseudoloma microsporidiosis in zebra danios.
  • Pleistophora infection and columnaris can produce similar white lesions in zebra danios.
  • Nipped fins among rival galaxy males.

Sources 877878879880

Understanding the animal

This species is part of a group that hobbyists, aviculturists or zoos keep widely (Danios and rasboras), so it's included for completeness. It may be rare in captivity itself, or not kept at all. Use the group guide as a starting point and look for species-specific advice from experienced keepers.
About this animal

About this animal

It is sexually dimorphic and, like other species in the genus, possesses a skeleton with fewer bones than the closely related zebrafish. However, it has a number of distinguishing features which differentiate it from others in the genus, with the most notable example being the conically projecting genital papilla between the funnel-shaped pelvic fins of males.

Quoted from the Wikipedia article “Danionella priapus” (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 livesLives in freshwater. Uses both the bottom and open water.
Water it lives inFreshwater.
ClimateTropical climate.
  1. FishBase species summary: Danionella priapus
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.

OverviewDanionella priapus is a species of Danionella endemic to India. It is sexually dimorphic and, like other species in the genus, possesses a skeleton with fewer bones than the closely related zebrafish. However, it has a number of distinguishing features which differentiate it from others in the genus, with the most notable example being the conically projecting genital papilla between the funnel-shaped pelvic fins of males. — Wikipedia (community-edited)
Where it livesHome 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

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

Average of sources0.6in
FishBase 1640.6
Seriously Fish species profiles 1670.6

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

Reported64–75°F
Seriously Fish species profiles 16764–75

Range the species tolerates; aim for the middle.

pH

Reported6–8
Seriously Fish species profiles 1676–8

Water hardness

Reported1–8dGH
Seriously Fish species profiles 1671–8

Minimum tank footprint

Reported18in
Seriously Fish species profiles 16718

Seriously Fish recommends a tank base of at least 18 × 12 in (about 11 US gallons).

Sources for this sheet

  1. 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.
  2. 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.
  3. Seriously Fish: Zebra danio (Danio / Brachydanio rerio) Experienced keeper or breederAdded in the 2026 source-checked care-guide review.
  4. Seriously Fish: Trigonostigma heteromorpha Experienced keeper or breederAdded in the 2026 source-checked care-guide review.
  5. Seriously Fish: Devario aequipinnatus Experienced keeper or breederAdded in the 2026 source-checked care-guide review.
  6. Seriously Fish: Danio / Celestichthys margaritatus Experienced keeper or breederAdded in the 2026 source-checked care-guide review.
  7. Wikipedia (species article) Community referenceFree encyclopedia; useful overviews with their own citations. Intro text is quoted under CC BY-SA 4.0.