Smudge-Spot Corydoras (Corydoras similis) Breeding Guide
How to breed Corydoras similis: cooler-water trigger, T-position spawning with eggs on the glass in high flow, hatch in 3-5 days, fry on microworm and brine shrimp.
Overview
Corydoras similis is found in the Rio Madeira basin in Brazil and reaches about 6 cm (2.4 inches). It is an egg-depositing catfish that spawns in the classic T-position, triggered by a cooler-water change.
Sexing
Females are noticeably rounder-bodied than males, particularly when carrying eggs, and are often also slightly larger.
Conditioning
Condition the fish on varied live, frozen and dried foods. Keep them within the species range of 21-27 degrees C (70-81 degrees F), pH 5.6-7.0 and a hardness of 0-12 dH.
Spawning Behavior & Trigger
Trigger spawning with a large (50-70%) water change using cooler water while increasing oxygenation and flow, repeated daily until the fish spawn. In the classic T-position the male grasps the female's barbels between his pectoral fin and body and releases sperm, which passes through the mouth and gills of the female toward her pelvic fins; she forms a basket to deposit a single egg, although up to 4 may be released. Eggs are typically laid on the tank glass, often where water flow is high.
Egg & Fry Care
The eggs hatch in 3-5 days. Once the yolk sacs are consumed the fry accept microworm and brine shrimp nauplii as first foods.