Breeding Corydoras gossei (Gosse's Cory)

Breeding guide for Corydoras gossei: sexing, conditioning, the warm-water spawning trigger, T-position mating and fry care.

Overview

Corydoras gossei is an armoured catfish (family Callichthyidae) from the Rio Mamoré watershed in Rondônia, northwestern Brazil, and likely northern Bolivia, reaching about 50–55 mm. It is an egg-depositor that spawns in the Corydoras T-position.

Sexing

Females tend to grow larger, and sexually mature individuals are noticeably broader and deeper-bodied than males, most obvious from above when females are full of eggs.

Conditioning

Condition adults on a varied diet of small live and frozen foods until the females are full of eggs. Use a male-to-female ratio of 2:1 or higher.

Breeding Setup

• Temperature: 24–28 °C
• pH: 5.5–7.5
• Hardness: 36–179 ppm
• Provide glass, fine-leaved plants and/or sunken spawning mops; mops are recommended for easy egg removal

Spawning Behavior & Trigger

Trigger spawning by performing a large (50–70%) water change with cooler water while increasing oxygenation and tank flow. Repeat daily until reproduction occurs. The female cups the sticky eggs between her pelvic fins, fertilises them in the T-position, and deposits them on glass, vegetation or a mop.

Egg & Fry Care

Incubation is normally 3–4 days. Once the yolk sacs are absorbed, fry accept small live foods such as microworm and Artemia nauplii. They require excellent water quality and perform better over sand than on a bare substrate.

Common Challenges

To prevent egg fungus, breeders typically add methylene blue or alder cones to the egg-rearing container.