Sterba's Corydoras

Geographic Origin and Biotope: Endemic to the Guaporé River basin on the border between Bolivia and Brazil. Inhabits placid river waters and seasonal forest pools, where the riverbed is studded with round pebbles, tangled driftwood, and accumulations of dead leaves that color the water (tannins).

Taxonomy and Morphology: Known as Sterba's Corydoras. One of the largest, most robust, and beloved Corydoras, capable of reaching and exceeding 6.5 cm (2.5 inches). The body possesses robust lateral bony armor; the snout is rounded (blunt profile), adorned with six powerful receptive barbels.

Social Behavior: Strong, hardworking, and very sociable. Sifts the sand incessantly, digging for hours. Kept in large groups (more than 6), it proves outgoing and an explorer. Often various specimens "pile up" on top of each other in the shade of a large plant to rest.

Coloration and Sexual Dimorphism: Dark body background (gray or brownish-black), covered with an intricate pattern of bright white polka dots, concentrated especially on the head. Its aesthetic signature is the fluorescent bright gold-orange coloration present on the pectoral (and sometimes pelvic) fins. Females are noticeably stockier and bulkier.

Aquarium Setup: Adapts to many sizes, but an 80x40 cm (32x16 inch) footprint is the bare minimum. An indispensable requirement is flooring made of fine rounded cosmetic sand, essential for the passage of food and the health of the mouth. Hiding places with Manila or mangrove roots. Lights shielded by floating leaves.

Diet and Feeding: Insatiable omnivorous detritivore, excellent "scavenger" if paired with specific foods. Should be fed directly at lights-out time with sinking wafers of meat and spirulina, bloodworms, daphnia, and tubifex. If food does not reach the bottom in sufficient quantity, it will slowly waste away.

Water Quality: It is the HIGH-TEMPERATURE CORYDORAS par excellence. Prefers waters between 24 and 28°C (75-82°F) (tolerating brief peaks up to 30°C/86°F). Ideal parameters: pH 6.0-7.6, low or medium hardness (GH 2-15). Extremely robust, but like all requires low levels of nitrates in the substrate.

Compatibility and Tankmates: The quintessential bottom companion for Discus (Symphysodon), thanks to its enormous tolerance for warm water. Excellent together with Angelfish (Pterophyllum), schools of Cardinal or Rummy-Nose Tetras, and peaceful tropical Loricariids. Ignored by large Cichlids thanks to defensive toxins and bony armor.

Aquarium Reproduction: Easily reproduced by providing abundant bloodworms and triggering the event with massive (40%) top-offs of decidedly colder water to simulate the Amazonian monsoon winter. They lay in the "T-position" (up to 300 adhesive eggs stuck to the glass in a strong current). Adults are egg devourers.

Risks and Diseases: The pectoral spines secrete a mild venom and can become inextricably tangled in nets, injuring both the animal and the keeper (very fine nets or rigid cups recommended). The use of sharp gravel is guaranteed to cause fatal infections to the barbels.