Mini Cory

Geographic Origin and Biotope: Endemic to Brazil and Suriname (Maroni and Corantijn river basins). Inhabits placid shady forest inlets, swamps, or small streams with mostly dark and amber waters, characterized by dense deposits of soft organic debris.

Taxonomy and Morphology: The name "nanus" describes its minute size: it belongs to the Callichthyidae family and hardly exceeds 4.5 centimeters (1.8 inches), placing it among the dwarf sizes of the corys. Stocky, rounded profile and standard lateral armor of the genus.

Social Behavior: Mild and perpetually busy on the bottom. Extremely gregarious, exhibits deep stress pathologies if left alone. It is mandatory to insert large swarms (from 8 to 15 specimens) to observe it moving in unison on the sand with total confidence.

Coloration and Sexual Dimorphism: Very elegant and striped design ("striped pattern"): brilliant silvery background on which 3-4 dense and continuous horizontal blackish stripes stand out. Females, as per the manual for the genus, appear visually clumsiest, wider, and stockier compared to the slender males.

Aquarium Setup: Abrasive substrates prohibited. Requires a base of fine sand, preferably dark to enhance the silver of the livery. Structure shady refuges with half coconut shells or tangles of branched roots, combining dim light on the surface.

Diet and Feeding: Debris micro-predator: the tiny mouth requires fine baits. Floating foods are not recommended. Excellent to provide sinking microgranules for Corydoras mixed with copious bi-weekly doses of frozen Daphnia, brine shrimp, white worms, and grindal worms.

Water Quality: Maintenance in the classic tropical ranges (22-26°C / 72-79°F). Soft hardnesses (GH 2-12) and weakly acidic-neutral water (pH 6.0-7.2). The degradation of the bottom and the accumulation of ammonia are ruthlessly fatal, demanding excellent filtration but mild flow.

Compatibility and Tankmates: Due to its stature, it is essential to pair it with peaceful mini-fish: Boraras, Hyphessobrycon, Nannostomus, and small Loricariids (Otocinclus). Never cross its path with rowdy fish, large Cichlids, Loaches, or nocturnal predators capable of swallowing it.

Aquarium Reproduction: Reproducible by stimulating the school with cold "monsoon changes" (temperature drops of 3-4 degrees). After frantic T-chases, the large adhesive eggs are fixed to the glass or on fine vegetation. Promptly remove eggs or parents to avoid their immediate ingestion.

Risks and Diseases: The erosion of the delicate barbels on inadequate bottoms causes lethal and inoperable fungal/bacterial necrosis of the mouth. Extreme hypersensitivity to medications containing copper sulfate or to high levels of prophylactic salinity.