Hardy does not mean maintenance-free
The peppered corydoras has a reputation as one of the toughest small catfish in the hobby — mottled, unshowy, tolerant of cooler water that would trouble fussier species. That reputation becomes a risk in old age, because the senior fish gets checked least. In truth its ageing follows the cory pattern: shorter foraging runs across the bottom, longer spells parked in a favourite hollow, surface dashes for air a touch less frequent, and a slow loss of plumpness if the food situation quietly stops working. Care changes are humble ones, done consistently: feed the floor, keep the floor clean, keep the group together.
The bottom is its whole world
Everything in this fish's life happens in the lowest inch of the tank, and the condition of that inch decides its old age. Smooth sand or fine, rounded substrate lets it sift without shredding the barbels it hunts by taste with; sharp or filthy beds wear those barbels down, and an old fish replaces lost condition slowly. Vacuum the open areas where waste settles — especially the corners it rests in — without churning the whole bed at once, and watch the barbels at feeding time. Full-length, busy whiskers on an actively sifting fish are the picture of a senior doing well.
Arranging for food to actually arrive
A peppered cory in a community tank eats what survives the descent, and old fish arrive at the fall zone last. Give the bottom its own ration: small sinking granules or broken wafers placed in the corys' working area after the main feed has the midwater fish occupied, a few times a week at minimum, daily for a fish visibly thinning. Softened foods are easier for an ageing mouth to manage than rock-hard pellets. Judge success from above — the healthy senior carries a gentle curve along the body, not a pinched waist behind the head — and adjust portions to what you see, not to a schedule written when the fish was young.
Company and cooler-water comfort
Peppered corydoras rest in loose contact with their own kind, and that social floor matters more, not less, to an old fish: keep the school at a proper size, and when numbers fall, add young peppered corys rather than letting the senior end its life as a singleton. Its tolerance for the cooler end of the tropical range remains an asset — an unheated-room tank that suits this species suits its old age too — but tolerance is not a licence for swings; a stable cool tank is kind, a yoyoing one is not, whatever the thermometer's extremes suggest the species can survive.
The quiet signs that call for help
Because this species hides decline so well, treat small deviations as worth a note and a water test: a cory sitting apart from the resting group day after day, barbels eroding on a clean bed, rapid breathing at rest, or a fish that no longer rises for its occasional gulp of air. If signs persist after water checks out, an aquatic veterinarian should see the record you have kept. Logging feeds, barbel condition, school numbers, and readings in KinsLe's Pet Passport gives this modest mottled catfish the documented senior care its toughness too often denies it.