Corydoras catfish look easygoing, and in a settled tank they mostly are, but a first-time carer can miss their needs precisely because those needs happen at the bottom, often after dark. Surface-feeding tankmates may eat everything before a single piece drifts down, and a helpful sitter who only watches at midday could report that the corys never fed at all. A good handover therefore covers the group, food that reaches the sand, the substrate itself, and the quiet behaviour changes worth reporting.
Start with the group and who eats where
Begin by writing how many corydoras you keep, what species they are if you know it, and where the group usually rests during the day, because a carer who knows the count can spot that someone is missing. Explain that corydoras are social fish that rest and forage together, so one fish tucked alone behind a plant all day is worth a second look rather than an instant panic. Note any tankmates and which of them are fast surface feeders, since that competition shapes how the evening feeding must be done. If one cory has a distinguishing mark or a slightly smaller size, describe it in plain words so the carer's reports to you are about an identifiable fish.
Sinking food, timing, and the lights-out meal
Food instructions are the heart of a corydoras handover. Name the sinking wafers, pellets, or frozen foods you use, state the exact number of pieces for the group, and give the feeding time you follow, ideally linking it to the evening when the corys become active. Tell the carer to scatter food across the front of the substrate rather than dropping it in one pile, and to check after a few minutes that pieces have reached the bottom instead of being intercepted. Warn against adding a second helping because the fish look busy; corydoras snuffle constantly whether or not they are finding food. If you rest the group from prepared food on certain days, write those days down rather than leaving the rhythm in your head.
Substrate, barbels, and gentle tank jobs
A corydoras carer should know why the bottom of the tank gets treated gently. Explain that the barbels around the mouth are delicate sensory organs the fish use to find food, and that you keep the sand or fine substrate clean with light surface siphoning during your normal water change, never deep digging near resting fish. Give your usual change volume and day, the conditioner you use, and an instruction to leave the filter media alone unless you ask otherwise. Mention that sudden darting to the surface for a gulp of air can happen occasionally in corydoras, but repeated frantic trips by several fish are different and belong on the call-you list.
Behaviour worth reporting and how to reach you
Close the care notes with observed baselines: how active your group is after feeding, how they rest together, and what normal breathing looks like at rest. Then list the changes you want reported the same day: a corydoras separated from the group and refusing food, visible damage or shortening of the barbels, redness around the mouth, several fish gasping at the surface, or cloudy water with a strong smell. Provide your number and a backup contact, and make clear the carer should add nothing to the water on a guess. That restraint protects the group far better than an improvised fix.
A corydoras handover written this way gives a newcomer confidence without turning the visit into an exam. Storing the group count, feeding scatter, and call-you signs in KinsLe's Care Pass lets your sitter pull up the approved bottom-feeding routine on the spot, even if your spoken briefing happened days earlier.