Hoplisoma trilineatum

A peaceful and hardy bottom-dwelling fish from South America, the Three Stripe Corydora is an excellent choice for community aquariums and beginner hobbyists. These social creatures thrive in groups and should always be kept with several of their own kind to feel secure and display their natural, active behaviors. As bottom-feeders, they spend their days exploring the lower levels of the tank, searching for food. Their diet is unfussy, and they readily accept a variety of sinking foods, such as pellets and wafers, but also enjoy occasional treats like frozen or live foods. They prefer a calm aquatic environment and are known for their easy-going temperament, making them compatible with a wide range of other small, peaceful fish. Their small adult size and low waste production make them a manageable addition to a well-maintained aquarium. They are quite resilient and can adapt to a broad range of water conditions, which adds to their popularity among aquarists of all skill levels. Occasionally, you may see them dart to the surface for a gulp of air, which is a normal and fascinating behavior for this species.

The Three Stripe Corydora is a quintessential benthic inhabitant originating from the slow-moving river systems of South America. This environment shapes its ideal aquarium setup, which should feature low water flow and a soft, fine substrate to protect its delicate barbels used for foraging. As an omnivore with a penchant for scavenging, its natural behavior involves constantly sifting through the substrate for morsels of food. In a home aquarium, this translates to a need for a varied diet consisting of high-quality sinking pellets and wafers, supplemented regularly with frozen or live foods to ensure balanced nutrition. This species is highly social and exhibits complex schooling behaviors, making it imperative to keep them in a group of at least six individuals. A proper school will reduce stress, encourage natural foraging, and allow them to thrive. Solitary specimens often become shy, withdrawn, and susceptible to poor health. These are moderately active fish that primarily occupy the a tank's bottom-dwelling zone. Their interactions with the environment include rooting around plants and consuming biofilm from surfaces, contributing to the tank's cleanliness. Physiologically, they are adapted for environments that may have lower oxygen levels, possessing the ability to breathe atmospheric air by quickly swimming to the surface. This is a normal, adaptive behavior and not necessarily an indicator of poor water quality unless it becomes excessively frequent. With a low metabolic rate and minimal waste production, their impact on the aquarium's bioload is relatively small for their size, but good filtration and regular maintenance remain essential for their long-term health. Due to their peaceful disposition, they can be housed with most other non-aggressive, similarly-sized community fish, particularly those that occupy the middle and upper water columns.

Hoplisoma trilineatum is a small, freshwater species belonging to the family Callichthyidae, a group of armored catfishes native to South America. It exhibits a fusiform body shape, which is laterally compressed and streamlined, typical for a benthic fish that navigates complex substrates. As a facultative air-breather, H. trilineatum possesses a modified, highly vascularized posterior intestine that allows it to utilize atmospheric oxygen. This physiological adaptation enables it to survive in hypoxic conditions that can occur in its natural habitat of slow-moving tributaries and floodplain lakes. Its ecological role is that of a benthic omnivore. Foraging behavior consists of using its sensitive barbels to detect and ingest a variety of food sources from the substrate, including detritus, microorganisms, and small invertebrates. In an artificial setting, this behavior manifests as the consumption of biofilm and sifting through aquarium substrate. The species displays a distinct social profile, forming schools which are crucial for its well-being and normative behavioral expression. Their metabolism and oxygen consumption rates are low, and consequently, they contribute a relatively low bioload to a closed aquatic system. H. trilineatum demonstrates a notable tolerance for a wide range of freshwater parameters, including a broad pH and water hardness spectrum, but shows minimal tolerance for salinity. It is strictly a freshwater species. From a conservation standpoint, the species is currently categorized with a status of Least Concern (LC) by the IUCN, indicating it is not presently at high risk of extinction in its natural range.

Breeding the Three Stripe Corydora is considered a moderately difficult but achievable endeavor for the dedicated hobbyist. To begin, sexing these fish can be challenging, though distinct differences become more apparent in mature, well-conditioned adults. Females are typically larger, broader, and more rounded in the body, especially when viewed from above, while males tend to be smaller and more slender. For successful spawning, a dedicated breeding tank is highly recommended, conditioned with a higher ratio of males to females, such as two or three males for every female. Conditioning the group for several weeks on a rich diet of high-quality live and frozen foods is crucial to bring the females into breeding condition. Spawning is often triggered by mimicking natural seasonal changes. A large water change of fifty to seventy-five percent with water that is a few degrees cooler than the tank's current temperature can simulate the onset of the rainy season and induce breeding behavior. During the spawning event, the fish become very active. Following a courtship chase, they will assume the characteristic 'T-position' where the female takes the male's milt into her mouth to fertilize the eggs she holds between her pelvic fins. As an egg-layer, the female will then deposit the adhesive eggs in small clutches onto various surfaces such as tank glass, filter intakes, or the leaves of plants. Because adult corydoras will predate on their own eggs and fry, it is essential to either remove the adults from the breeding tank or move the eggs to a separate, well-aerated rearing tank. The fry will hatch after a few days and initially subsist on their yolk sacs. Once the yolk sac is absorbed, they must be fed microscopic foods like infusoria or liquid fry food, progressing to newly hatched brine shrimp and crushed flake food as they grow. Maintaining pristine water quality through small, frequent water changes is critical for the survival and healthy development of the fry.