Spares for corydoras catfish are calculated for a group, not an individual: these social bottom dwellers live in schools, eat from the substrate, and depend on steady aeration near the bottom where oxygen runs thinnest. A two-week reserve sized to the whole school, plus backup air and a safe moving container, covers the realistic emergencies — an outage, a cracked tank, or a short evacuation.
Sinking food, counted for the whole school
Two weeks of sinking food is the reserve target for corydoras. Their meals are wafers and small pellets that fall to the bottom, so count the school's actual daily portion — how many wafers disappear in a feeding — and multiply by fourteen, then round up to one full unopened package of each staple. Keep the texture variety they already know, since corydoras root through food with sensitive barbels and a familiar wafer gets eaten while a novel one may be ignored. Store the packages sealed and dry; bottom-feeder wafers absorb moisture and crumble quickly once a bag sits open in a humid fish room.
Air first: the corydoras-specific equipment risk
A backup air supply matters more for corydoras than for most community fish. When power fails, oxygen depletes fastest in the lower water where corydoras live and feed, and stressed corys dart to the surface to gulp air far more often than usual — an early warning sign. Store a battery air pump, fresh batteries, and an airstone so the bottom layer stays oxygenated through an outage. Add a spare thermometer and a full bottle of water conditioner, since any emergency move means fresh conditioned water, and corydoras tolerate poorly mixed or untreated water badly.
A smooth container, because barbels are fragile
The transport piece of the corydoras kit is a smooth-bottomed tub, chosen deliberately. Corydoras explore with the whisker-like barbels around their mouths, and rough gravel or a coarse net can wear those barbels down, leaving the fish struggling to find food afterward. The emergency tub should have a bare, smooth floor or a thin layer of smooth sand, a secure lid, and enough size for the whole school to move together — splitting a school between containers stresses fish that calm each other by grouping. Pack a soft, fine-mesh net for the same reason: barbels and fin spines catch in coarse mesh.
Check the shelf against the school you actually have
Corydoras schools grow by addition and shrink by loss, and the spare shelf should match the current count. Recheck the reserve whenever the group changes: a school that grew from six to ten needs more wafers in the fourteen-day count and a bigger tub than the old plan assumed. Test the battery pump, confirm the conditioner bottle is genuinely full rather than nearly empty, and replace food packages that have sat opened past their freshness. A corydoras that stops foraging, hides through feeding time, or shows visibly shortened barbels deserves an aquatic veterinarian's advice rather than a wait-and-see approach.
Put the inventory where the whole household sees it
The person home when a tank cracks may not be the person who stocked the shelf. Write the corydoras inventory — food location, tub location, pump and battery location, and the school's current head count — where every family member who helps with the fish can reach it, and walk a second person through the shelf once so the knowledge is not theoretical. That is the habit KinsLe's Family Sharing is built around: the corydoras profile and its care information stay shared with the family who help, so the spares get found and used correctly on the first try.