A corydoras spawning looks like a celebration: the shoal races, pairs form the classic T-position, and the female, carrying a few eggs at a time cupped in her fins, dashes off to glue them to the glass or a leaf. Those scattered, sticky eggs are your nursery. Raising corydoras from them is gentle, methodical work that suits patient keepers perfectly.
Finding and Collecting the Eggs
Search the tank systematically once spawning activity settles: glass panes, broad leaves, filter housings and corners are the usual sites, and eggs are easy to miss because each cluster holds only a few. Many breeders leave eggs where they lie if the tank houses only the corydoras themselves and plenty of cover, but egg-eating tankmates — including, sometimes, the parents — make collection safer. Roll each egg gently off its surface with a clean fingertip; they are tougher than they look, with a tacky coating that will stick them to the side of a hatching container instead. Work slowly and count sites rather than eggs, so you know when the search is complete.
The Hatching Container
A small container of water taken from the parents' tank, floated or placed where it holds the same temperature, is the classic hatchery. Add a gentle air stone so water moves softly over the eggs, mimicking the fanning and current that keep wild eggs clean. Inspect daily with a magnifier if you like — healthy eggs stay translucent amber and darken as embryos develop — and remove any egg that turns opaque white or grows a fuzzy coat, since fungus walks from egg to touching egg. Do not scrub, disturb or rearrange; cleanliness and airflow do the work. Hatching fry drop to the bottom and rest, yolk sacs attached, looking like tiny tadpoles with whisker buds.
First Days on the Bottom
New corydoras fry are bottom fish from their first hour. They absorb their yolk sacs over the first couple of days, after which they need food on the floor of their world: infusoria, microworms and finely powdered fry food dusted across a bare or thinly sanded bottom they can graze without competition or hiding places for waste. Keep the bottom siphoned with fine tubing — debris at fry level is a constant threat at this size. Within days the fry begin the family trade of sifting and shuffling, barbels growing in, and slightly larger foods such as baby brine shrimp can join the menu.
Growing On With the Shoal in Mind
Raise the youngsters in their group; corydoras confidence is collective from the very start. As they grow, graduate them to a larger nursery with fine sand, gentle flow and the sinking foods they will eat for life, and introduce them to the adult shoal only when they are too big to be mistaken for snacks by any tankmate. Growth is steady rather than spectacular, and pattern and finnage develop gradually over weeks. Sharing the daily egg inspection, fungus checks and dusting feeds through KinsLe Care Teams, where each small duty is assigned and ticked off, keeps your baby corydoras' fragile first days under constant gentle watch.