Daily attention to the floor a corydoras lives on
A corydoras experiences its tank from the bottom up, so daily care in its aquarium means watching the floor. After feeding, check that sinking wafers and pellets are being eaten rather than dissolving into the substrate, and siphon or lift out what remains once the group loses interest. Corydoras push their mouths into the top layer of sand or fine gravel all day, and decaying food in that layer sits directly against their barbels, the whiskers they taste and navigate with. A quick daily pass with a small siphon over the feeding area does more for this fish than any amount of attention to the upper water, which the group visits only in quick darts to the surface.
The weekly vacuum: surface only, in slow passes
The central weekly task for a corydoras tank is vacuuming the substrate surface without excavating it. Move the siphon in slow, overlapping passes just at the top layer, lifting the mulm and waste that settle where the fish feed, and resist plunging the tube deep, which clouds the water, buries waste further down, and can drag across resting fish. Work half the floor one week and the other half the next if the group is shy, leaving a familiar, undisturbed resting area under plants or wood where the school regroups. Replace the removed water with conditioned water matched in temperature, poured onto a rock or dish so the current does not sandblast the freshly cleaned floor the corydoras are about to sift. A turkey baster makes a useful spot tool during this work, puffing debris out of plant roots into open water where the siphon can collect it before it resettles onto the sand.
Sand, barbels, and the details cleaning must protect
Substrate choice and cleaning style meet in a corydoras tank at the fish's mouth. Sharp or coarse gravel wears barbels down, and once worn, a cory struggles to feed well in the very tank that injured it, so if your substrate is rough, keep its surface especially clean while you plan a gentler replacement. During cleaning, avoid chasing individual fish with the siphon; a startled corydoras darts unpredictably and can strike glass or decor. Wipe the front glass, rinse filter media in removed tank water, and keep flow consistent, because this bottom-oriented group still depends on well-oxygenated water moving down to their level, particularly overnight.
Signs the floor routine needs adjusting
A corydoras group tells you the floor routine is failing through its barbels and its posture. Shortened or missing barbels, redness around the mouth, fish resting tilted on the substrate, or a group that stops its busy evening sifting are all reasons to clean the surface more attentively and review the substrate itself. Occasional single losses happen in any tank, but several corydoras going quiet together after a change suggests the replacement water differed too much or the disturbance ran too long, and an aquatic veterinarian's advice is worth seeking if the pattern repeats. KinsLe's Care Teams feature can place substrate care with whoever is home during the school's quietest hour, a logged finish preventing a second stirring that day.