Gold Laser Corydoras (Corydoras melanotaenia) Breeding Guide

Breeding Corydoras melanotaenia (gold/green laser cory): sexing by body shape, T-position spawning, a cool water-change trigger, eggs on glass and fry care over sand.

Overview

Corydoras melanotaenia (often sold as the gold or green laser cory, CW009) is a South American corydoras that breeds following the classic egg-depositing T-position method common to the genus, with eggs laid on solid surfaces and no parental care.

Sexing

Females are noticeably rounder and broader-bodied than males, especially when full of eggs, while males remain slimmer.

Conditioning

Condition the fish on varied live, frozen and dried foods using a ratio of about two males per female. A breeding tank around 18 x 12 x 12 inches with a bare, sand or fine-gravel bottom works well, with reported conditions of about 24 °C (75 °F) and pH around 6.5.

Breeding Setup

Eggs are usually laid on the tank glass, often in an area of higher water flow, so leave clear glass surfaces available. A thin sand layer is preferable for the fry stage.

Spawning Behavior & Trigger

Trigger spawning with large 50-70% water changes using cooler water while increasing oxygenation and flow, daily until spawning. A receptive female lets the male caress her with his barbels before adopting the classic T-position, in which the male grasps the female's barbels between his pectoral fin and body; he releases sperm toward her pelvic fins, which form a basket holding single eggs (up to about four may be released at a time).

Egg & Fry Care

Eggs hatch in around three to five days. The fry accept microworm and brine shrimp nauplii as first foods and seem less susceptible to disease when kept over a thin layer of sand rather than in a bare-bottomed setup.

Common Challenges

Maintaining good water quality during the fry stage and providing appropriately small first foods are the main practical concerns, as with most egg-depositing corydoras.