Corydoras arcuatus

Adult fish of this species reach approximately 5 cm in length. A striking distinguishing feature is a broad dark stripe on a lighter background, which starts at the mouth, passes through the eyes along the upper part of the body, and gracefully curves towards the lower part of the tail base, forming a characteristic arch. The same coloration can be found in Corydoras metae, which often leads to confusion between these species. Sexual dimorphism in these fish is very weak, making it quite difficult to distinguish between males and females.

Corydoras arcuatus inhabits the upper reaches of the Amazon River basin in Brazil and Peru. In nature, it lives in areas of water bodies with slow currents, muddy bottoms, and an abundance of organic debris. It prefers places with soft water and dense vegetation that provides shelter.

A peaceful schooling species, primarily active at dusk and night. The fish are bottom-dwellers and should be kept in groups of at least 5–6 individuals; when alone, they become timid and stressed. They are well compatible with other peaceful aquarium inhabitants of a similar size.

A school of these fish requires an aquarium with a volume of at least 60–70 liters. Soft sand or fine rounded gravel should be used as substrate, as sharp substrate can damage the sensitive barbels of the catfish. Live plants, driftwood, and caves are essential to create shaded areas. Filtration and aeration should be effective but without creating a strong current. Weekly partial water changes with fresh water are required.

This is an omnivorous species, feeding on small benthic invertebrates and organic matter in nature. In the aquarium, specialized sinking tablets for catfish should be used, supplementing the diet with live or frozen foods such as bloodworms, brine shrimp, or tubifex. Food must reach the bottom, as the fish feed exclusively in the bottom layer.

Breeding is possible in a separate spawning tank with soft, slightly cooler water. Frequent water changes and abundant protein feeding serve as a stimulus. The female lays eggs on smooth surfaces, such as broad plant leaves or the aquarium glass. After spawning, it is recommended to remove the parents to prevent them from eating the eggs.

The species is sensitive to water quality; if keeping conditions are violated, bacterial infections often develop, affecting the barbels and skin. They are characterized by sharp spines in their fins, which can get caught in a net during transfer. Prevention involves maintaining clean substrate and stable water parameters.

When choosing, pay attention to the fish's activity and the integrity of its barbels, which should be long and without signs of erosion. A healthy specimen has clean coloration, a robust body without visible ulcers, spots, or fin damage. Avoid purchasing fish that appear emaciated or apathetic.