Breeding Corydoras osteocarus

Breeding Corydoras osteocarus: water parameters, egg laying in vegetation, up to 300 eggs, and a 3-4 day hatch at ~21 C.

Overview

Corydoras osteocarus (also placed in the genus Hoplisoma) is a callichthyid catfish of the Orinoco River basin in Colombia and Venezuela, with FishBase also listing coastal rivers in Suriname. It reaches about 4.0-4.1 cm SL. Recorded water tolerances are pH 6.0-8.0, hardness 2-25 dH, and a temperature of roughly 21-25 C.

Breeding Setup

Within the recorded tolerances (pH 6.0-8.0, 21-25 C, soft to moderately hard water), provide dense, fine-leaved vegetation, since this species attaches its eggs to plants. Adults do not guard the eggs.

Spawning Behaviour & Trigger

The species lays eggs in dense vegetation. As in other Corydoras, a large cooler water change with increased oxygenation and flow is the usual spawning trigger; the documented outcome below is the species-specific record for egg numbers and hatch timing.

Egg & Fry Care

In captivity the species produces up to about 300 eggs, which it usually attaches to plants. Hatching occurs in about 3-4 days at 21.4 C (70.5 F). Because adults do not guard the eggs, eggs and fry are best separated from the parents to prevent predation.

Common Challenges

With large clutches, fungal loss of infertile eggs is a common issue; removing fungused eggs and maintaining clean, well-oxygenated water supports a higher hatch rate.