Wavy Cory

Corydoras undulatus is a subtly attractive species from the La Plata basin in southeastern South America, including parts of Brazil and Argentina. Its common name derives from the undulating, wave-like pattern of brown and cream markings that run along its flanks, creating a marbled effect that is more delicate and intricate than the bold spotting or striping seen in many other cories.

As a southern hemisphere species from a subtropical drainage, C. undulatus tolerates cooler temperatures than Amazon-basin cories and can be kept at 20–25°C. This makes it suitable for slightly cooler aquaria and potentially for mixed setups that include other subtropical South American fish.

C. undulatus is rarely traded but occasionally appears through importers specialising in La Plata basin species. Care is beginner-accessible: it is hardy, tolerates a broad water chemistry range, and adapts readily to aquarium life. Keep in groups of at least six with standard cory husbandry: fine substrate, regular water changes, and varied sinking foods.

Water: Soft to moderately hard, pH 6.0–7.5, temperature 20–25°C; cooler than Amazon species; subtropical tolerant. Tank: 60 L with fine sand or smooth gravel, plant cover, and good filtration; suitable for subtropical setups. Feeding: Sinking pellets, frozen bloodworm, Daphnia, and blanched greens; varied diet important. Breeding: Typical cory spawning; cooler water trigger particularly effective given subtropical origin. Compatibility: Peaceful with all community species; suitable for subtropical community tanks.