Eques Corydoras / Horseman's Cory
Corydoras eques
Known as the 'Horseman's Cory'. One of the rarest, most expensive, and coveted Corydoras in the world. Features an unusual solid emerald-green metallic body, broken by a blinding neon-orange collar behind the nape.
Water Temperature
22 - 26 °C
pH Value
6 - 7.2
Water type
Freshwater
Tank level
Bottom
Adult size
5.5 cm
Minimum tank volume
>= 60 L
Minimum group
>= 6
GH
2 - 12 dGH
KH
1 - 6 dKH
TDS
40 - 240 ppm
Conductivity
63 - 375 uS/cm
Species description
Geographical Origin and Habitat: Amazon River basin (Brazil). Inhabits open waters in clear streams and shaded oxbow lakes, with sandy bottoms and the presence of fallen branches and leaves.
Taxonomy and Morphology: Horseman's Corydoras (Corydoras eques). Species with a relatively short snout, whose name ("horseman") refers to the elegant orange/rust band that crosses the head and back like a cloak.
Social Behavior: One of the most distinctly schooling species: the synchronized swimming of a large group of C. eques is spectacular. Very peaceful, they spend the day methodically exploring the sand.
Coloration and Sexual Dimorphism: Spectacular base coloration of dark metallic green/blue on the flanks, in sharp contrast with the vivid burnt orange (or rust-colored) band covering the nape, part of the back and pectoral fins. Females more robust.
Care, breeding and tankmates
Aquarium Setup: Very fine sand bottom is mandatory to protect the barbels and allow natural digging. The addition of dry leaves and roots that slightly amber the water will enhance the metallic coloration.
Diet and Feeding: Micro-predator. Likes live or frozen food such as brine shrimp, tubifex and daphnia, but easily gets used to sinking dry feeds and specific tablets for bottom fish.
Water Quality: Sensitive to nitrate pollution and bottom cleanliness. Requires clear, soft and slightly acidic waters, well filtered but with non-excessive currents on the bottom.
Compatibility and Cohabitation: Excellent inhabitant for peaceful South American tanks. Ideal together with peaceful upper-zone fish (Tetras, Hatchetfish) and dwarf Cichlids that are not too aggressive on the bottom.
Aquarium Breeding: Not very easy. Requires rainy season simulations with massive cold water changes to trigger the amorous chases and the adhesion of eggs on glass or plants.
Risks and Diseases: Extremely susceptible to barbel corrosion and subsequent fungal infections if kept on sharp gravel or in aquariums with poor bottom maintenance.
Geographic Origin and Distribution
Amazon River basin (Brazil). Inhabits open waters in clear streams and shaded oxbow lakes, with sandy bottoms and the presence of fallen branches and leaves.
Origin
Amazon, Orinoco, and Guianas
Fish profile
- Temperament
- Semi-aggressive
- The temperament of Corydoras eques can only be described as completely peaceful and highly gregarious. They are a schooling fish by nature and absolutely must be kept in groups of at least six individuals of their own kind to feel secure. When kept in insufficient numbers, they will become extremely stressed, reclusive, and susceptible to disease. In a proper school, they are active, inquisitive, and highly entertaining to watch as they scurry around the bottom together like a busy little cleaning crew. They pose absolutely no threat to any other inhabitants in the aquarium.
- Diet
- Omnivore
- In the wild, Corydoras eques is a micro-predator and scavenger that sifts through the substrate for small insects, worms, and crustaceans. In the aquarium, they readily accept a wide variety of high-quality sinking foods, including pellets, wafers, and granules designed for bottom feeders. To ensure optimal health and coloration, their diet should be supplemented with live or frozen foods such as bloodworms, daphnia, and brine shrimp. They are not true algae eaters, so feeding them solely algae wafers is a common mistake that can lead to malnutrition. A varied diet will keep their immune system strong and encourage natural foraging behaviors.
- Life expectancy
- 5-8 years
- This fascinating and colorful species has an average lifespan in captivity of about 5 to 8 years if housed in proper conditions. A well-filtered aquarium, consistent water changes, and the absence of nitrates are essential to keep them healthy. Proper maintenance of the sandy substrate prevents lethal bacterial infections, extending their lifespan.
- 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 4.8 cm for this species, recorded as standard length (SL). The taxonomic record consulted is Corydoras eques (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
- School
- When keeping Corydoras eques, the exact sex ratio is not strictly critical for their day-to-day well-being, as they do not exhibit aggression toward each other. However, if the goal is to breed them, a ratio of two or three males for every female is strongly recommended. This multiple-male approach increases the chances of successful fertilization during the spawning process. Females are typically larger and noticeably broader when viewed from above, especially when conditioned with high-quality foods. Maintaining a healthy, mixed-gender school allows for the observation of their fascinating natural social dynamics.
- Feeding frequency
- Twice daily
- It is generally recommended to feed Corydoras eques small amounts of food once or twice a day. The key is to provide only what the fish can completely consume within a few minutes to prevent uneaten food from rotting in the substrate. Because they are bottom feeders, you must ensure that enough food reaches the bottom before faster mid-water fish consume it all. If feeding twice a day, offering a staple sinking pellet in the morning and a frozen treat in the evening works exceptionally well. Observing their bellies can help you gauge if they are getting enough food; they should look gently rounded but not bloated.
- Bioload
- The bioload of Corydoras eques is relatively low to moderate, making them an excellent choice for a community aquarium. They do not produce excessive amounts of waste compared to larger or more predatory fish. However, because they are a schooling species and should be kept in groups, the cumulative bioload of the school must be accounted for when sizing the filtration system. Regular water changes and a properly cycled aquarium are still essential to maintain the high water quality they require. It is important to avoid overfeeding, as uneaten food will negatively impact the water parameters.
- Flow
- Stagnant
- Corydoras eques appreciates a moderate amount of water flow in the aquarium, simulating the gentle currents of their native South American streams. The flow should be strong enough to keep the water well-oxygenated and prevent detritus from settling on the bottom, but not so strong that the fish struggle to swim or rest. Using a standard hang-on-back or canister filter usually provides the perfect amount of water movement. They will often be seen actively swimming against the current for exercise, but they also need quiet resting areas among plants or hardscape. Providing a balance of moving water and still zones is the best approach to their habitat.
- Reproduction
- Oviparous
- Breeding Corydoras eques in captivity is entirely possible and often highly rewarding for dedicated aquarists. They are egg scatterers, typically laying their adhesive eggs on broad-leaved plants, aquarium glass, or smooth stones after an elaborate courtship dance. To trigger spawning, aquarists often perform a large, cool water change to simulate the onset of the rainy season in the Amazon basin. Once the eggs are laid, the parents provide no parental care and may even consume their own eggs if not removed. For the best survival rate, the eggs should be transferred to a separate rearing tank and the fry fed infusoria or freshly hatched brine shrimp.
- Compatibility & tankmates
- Corydoras eques is incredibly peaceful and makes a fantastic addition to most community tanks. They get along well with other peaceful, similarly sized fish such as tetras, rasboras, and dwarf cichlids. It is crucial to avoid keeping them with large, aggressive, or predatory species that might view them as food or nip at their fins. They are also completely safe to keep with most ornamental snails and adult dwarf shrimp, although baby shrimp might occasionally be eaten. Their bottom-dwelling nature means they rarely compete for space with mid- or top-dwelling tank mates.
- Tank level
- Bottom
- As classic bottom-dwellers, Corydoras eques will spend nearly all of their time foraging and resting on the substrate. They use their sensitive barbels to meticulously search the sand or fine gravel for any edible morsels that have sunk to the bottom. While they are primarily benthic, it is completely normal to see them periodically make lightning-fast dashes to the water's surface to take a gulp of air. Aside from these quick trips to the top, they will almost never be found swimming in the middle or upper levels of the water column. Providing a large footprint with plenty of open bottom space is far more important than tank height.
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)
- 0.5039
- Bayesian Length-Weight
- a = 0.00741, b = 3.14
- VulnerabilityLow vulnerability (10 / 100)
Image gallery
Licensed images linked to the species or, when marked, to the closest representative taxon.
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Recommendations grouped by close relatives, companion choices, and similar care.
