Northern Cory
Corydoras septentrionalis
Slender and graceful Venezuelan Cory. Metallic greenish livery, with a diffuse and dense dark dotting that thickens to form indistinct dark spots on the caudal peduncle.
Water Temperature
22 - 26 °C
pH Value
6 - 7.5
Water type
Freshwater
Tank level
Bottom
Adult size
5.5 cm
Minimum tank volume
>= 80 L
Minimum group
>= 6
GH
2 - 12 dGH
KH
2 - 10 dKH
TDS
50 - 280 ppm
Conductivity
78 - 438 uS/cm
Species description
Geographical Origin and Habitat: Endemic to the northern Orinoco River basin, between Venezuela and Colombia (hence "septentrionalis" = northern). Inhabits quiet river oxbows, residual pools, and slow, shaded streams with sandy or muddy bottoms.
Taxonomy and Morphology: Northern Corydoras (Corydoras septentrionalis). Belongs to the long-snouted Corydoras group. Features an elongated and pointed cranial profile which it uses to probe deeply into the substrate in search of hidden prey.
Social Behavior: Highly gregarious. Despite being slightly larger than other Corys, it is extremely peaceful. The group (minimum 6-8 specimens) constantly explores the bottom in a loose formation, always maintaining visual contact.
Coloration and Sexual Dimorphism: Light base livery covered by a dense network of dark spots and very fine wavy lines extending over the snout and body. Barred caudal fin. Adult females are plumper, with a visibly swollen abdomen.
Care, breeding and tankmates
Aquarium Setup: Very fine sand is an essential requirement, even more so than for short-snouted Corydoras, since this species literally buries its entire snout in the substrate to feed. Add roots to create hiding places.
Diet and Feeding: Benthic omnivore. The shape of its snout makes it an excellent extractor of hidden bloodworms and tubifex. Accepts quality pellets for bottom fish, but has a higher protein requirement derived from live/frozen prey.
Water Quality: Adapts well to both weakly acidic and neutral waters (pH 6.0-7.5), but is uncompromising on bottom hygiene. Accumulation of detritus and nitrates causes bacterial infections to the long sensory barbels.
Compatibility and Cohabitation: Ideal companion for Orinoco biotopes. Perfect with Tetras (e.g. Cardinals, Hemigrammus), Hatchetfish on the surface, and quiet Loricariids. Avoid large or medium Cichlids (e.g. Geophagus) that compete for the bottom.
Aquarium Breeding: Achieved with drastic cold water changes that simulate the onset of the wet season. The female lays very large, adhesive eggs on the leaves of strong plants or on the glass, in areas with strong current.
Risks and Diseases: Vulnerable to barbel wear caused by sharp gravel bottoms. Copper compounds and anti-snail medications can quickly prove lethal given their scale-less anatomy.
Geographic Origin and Distribution
Endemic to the northern Orinoco River basin, between Venezuela and Colombia (hence "septentrionalis" = northern). Inhabits quiet river oxbows, residual pools, and slow, shaded streams with sandy or muddy bottoms.
Origin
Tropical oceans and reefsAmazon, Orinoco, and GuianasNorth America
Fish profile
- Temperament
- Semi-aggressive
- The temperament of Corydoras septentrionalis is exceptionally peaceful and highly social in nature. They must be kept in groups of at least six individuals to thrive. In proper schools, they are confident and constantly active across the bottom.
- Diet
- Omnivore
- The diet of Corydoras septentrionalis primarily features benthic organisms and small detritus. In captivity, they eagerly eat sinking pellets and high-quality bottom-feeder wafers. Live foods like bloodworms and daphnia should be offered for optimal health.
- Life expectancy
- 3-5 years
- In captivity, the Northern Longnose Cory has an average lifespan of 3 to 5 years under optimal aquarium conditions, though some well-maintained individuals can reach up to 8 years. Providing a stress-free environment, stable water chemistry, and a clean substrate is essential for maximizing their longevity. Regular water changes and a high-quality, diverse diet are critical factors in preventing premature mortality in this species.
- Adult size
- 5.5 cm
- The catalog's scalar value is 5.5 cm. The FishBase SPECIES table (v25.04 snapshot) source reports a maximum adult measurement of 4.9 cm for this species, recorded as standard length (SL). The taxonomic record consulted is Corydoras septentrionalis (v25.04); male or unsexed record. These figures are not interchangeable: the first is the profile's editorial reference, whereas the second is a published maximum under a specific measurement convention; differences among sources can reflect sex, population, life stage and measuring method.
- Sex ratio
- Specific M:F ratio
- A specific sex ratio is unnecessary for the general community keeping of Corydoras septentrionalis. For dedicated breeding, a ratio of two males per female is optimal. Females are visibly rounder and broader, while males are slender.
- Feeding frequency
- Twice daily
- It is recommended to feed Corydoras septentrionalis one or two times daily in moderate portions. Ensure the food reaches the substrate before mid-water fish consume it all. Feeding just before lights out helps them forage peacefully without stress.
- Bioload
- The bioload of Corydoras septentrionalis is relatively low compared to larger tank mates. Since they are schooling fish, their combined waste can accumulate over time. Consistent filtration and weekly water changes are necessary for maintaining clean water.
- Flow
- Stagnant
- Corydoras septentrionalis prefers a moderate water flow that replicates gentle Amazonian streams. This circulation thoroughly oxygenates the water and prevents detritus accumulation. Calm resting zones should also be provided for relaxation.
- Reproduction
- Oviparous
- Breeding Corydoras septentrionalis in an aquarium is highly achievable with proper conditioning. Spawning is typically triggered by a large, slightly cooler water change. The female then deposits adhesive eggs on aquarium glass or broad plant leaves.
- Compatibility & tankmates
- In terms of compatibility, Corydoras septentrionalis is extremely peaceful and ideal for community setups. They coexist perfectly with small tetras, rasboras, and dwarf cichlids. Large, aggressive bottom-dwellers must be avoided to prevent undue competition.
- Tank level
- Bottom
- As obligate bottom-dwellers, Corydoras septentrionalis spends the vast majority of its time on the substrate. They constantly search for food by sifting fine sand with their sensitive barbels. They occasionally dart to the surface to gulp atmospheric air.
Scientific Parameters & Models
FishBase
Window to the official scientific data of the species
Data synced on: 06/15/2026
- Trophic level
- 3 ± 0.3 se
- Resilience
- High (less than 15 months)
- Phylogenetic uniqueness (PD50)
- 0.5
- Bayesian Length-Weight
- a = 0.01778, b = 3.02
- VulnerabilityLow vulnerability (10 / 100)
Image gallery
Licensed images linked to the species or, when marked, to the closest representative taxon.
Related species
Recommendations grouped by close relatives, companion choices, and similar care.
