Pigmy Corydoras

Adults of this fish typically reach a length of 5 to 6 cm. Their bodies are gray and adorned with numerous black speckles that extend to the tail. Two dark stripes are visible on the head and dorsal fin. A distinctive feature is a somewhat elongated snout.

The species inhabits South America, in the Inírida River basin and the upper Orinoco River in Colombia. It lives in freshwater bodies with soft, slightly acidic or neutral water, preferring areas with slow currents and sandy or fine-gravel bottoms.

A peaceful schooling fish, primarily active during twilight hours. For their comfort, it is recommended to keep a group of 5–6 or more individuals. These catfish are bottom-dwellers, constantly exploring the substrate for food. They get along well with other non-aggressive species, but due to their activity, they may disturb less mobile tankmates.

This fish is undemanding and quite easy to keep, adapting readily to a wide range of conditions. Corydoras delphax can feel comfortable in both slightly acidic and slightly alkaline water, tolerating low to medium hardness levels. An ideal home for them would be an aquarium of 80 liters or more, equipped with soft sandy substrate and several hiding places. It is crucial to ensure consistently warm and clean water, preventing the accumulation of organic waste—food remnants, excrement, and decaying plant matter. Maintaining biological balance directly depends on the proper functioning of equipment, particularly the filtration system, as well as regular mandatory aquarium maintenance procedures. Such procedures include weekly partial water changes with fresh water, as well as cleaning the substrate and decor elements. As for feeding, Corydoras delphax is an omnivorous species that readily accepts most standard aquarium foods of appropriate size. The only condition is that the food must be sinking, as these catfish prefer to spend most of their time in the bottom layers. In terms of behavior and compatibility, the Pigmy Corydoras is peaceful, getting along excellently with both its own kind and other fish species. Thanks to its high adaptability, it is perfectly suited for most freshwater aquariums. These fish feel most comfortable in groups of 4 to 6 individuals.

An omnivorous species, in nature it feeds on small invertebrates, insect larvae, and detritus. In the aquarium, it readily eats high-quality sinking foods: specialized tablets for catfish, frozen or live foods such as bloodworms, daphnia, and brine shrimp. Feeding is recommended once a day, shortly before the lights are turned off.

Breeding occurs by laying eggs on a substrate, often on broad plant leaves or aquarium glass. Water changes to softer and cooler water, simulating the rainy season, stimulate spawning. Parents do not care for their offspring and may eat the eggs, so it is recommended to remove the adults after spawning.

These fish have strong immunity but are sensitive to water quality and substrate condition. The main problem is damage to their delicate barbels due to the use of sharp or coarse substrate, which opens the way for bacterial infections. The species tolerates elevated nitrate concentrations and the use of salt in aquarium water poorly.

When purchasing, choose active fish with clean skin without spots or damage. It is important to pay attention to the condition of the barbels: they should be intact, without signs of erosion or inflammation. Healthy individuals should show interest in foraging for food on the bottom, rather than appearing apathetic or emaciated.