Barbels first in any corydoras diary entry
A corydoras catfish diary should open with the barbels, because those whiskers around the mouth are this fish's feeding tools and its most honest health signal. Note whether each fish's barbels look long and flexible or shortened, stubby, and worn, and compare against a photo from earlier weeks if you keep one. Healthy corydoras push their snouts into soft substrate and sift constantly while foraging, so record how much of the evening the group spent digging versus sitting still. Add the substrate type and when you last vacuumed it, since a dirty or sharp bed explains barbel wear that might otherwise be mistaken for illness.
Group behaviour and surface trips to log
Group behaviour defines a corydoras catfish entry, because these are shoaling fish that rest, forage, and explore together. Count the group and note whether everyone joins the loose, whiskery huddle at rest or one fish sits apart under a leaf. Occasional quick dashes to the surface are normal for this species, which gulps air, so record frequency honestly: a few trips in an evening is ordinary, while constant surface visits alongside rapid gill movement suggest the water needs testing that day. Note playful mid-water swims after a water change too, a classic corydoras response worth logging as a positive sign rather than a worry.
Feeding, body shape, and breeding notes
Feeding notes for a corydoras catfish should say whether the sinking food actually reached the bottom and how long the group worked over it. Log the foods offered, whether faster tankmates stole the share, and whether each fish's belly looks gently rounded afterwards rather than pinched behind the head. Record the classic T-position spawning, eggs placed on glass or leaves, and how many you left or moved, since breeding weeks change appetite and activity in ways that look odd without context. Pair every entry with water test results, temperature, and any new fish added, because corydoras react quickly to unstable or freshly cycled conditions.
Skin, fin, and resting signs to describe precisely
A corydoras catfish has armour plating instead of ordinary scales, so describe what you see on that plating in specific terms. Note red or inflamed patches along the flank or belly, fuzzy growths, frayed dorsal or tail fins, and eyes that look sunken or cloudy. Write down prolonged stillness with fins clamped tight to the body, loss of balance while resting on the substrate, or a fish that no longer rights itself briskly when disturbed. These details, dated weekly, let you show whether a patch is spreading or stable, which is exactly the distinction that decides how urgently to act.
When corydoras diary notes call for advice
Barbel loss combined with poor feeding, red patches, repeated surface gasping, or a fish separating from the shoal should move a corydoras catfish entry from routine logging to prompt advice seeking. Test the water first and write the results beside the symptoms, then contact an aquatic veterinarian or experienced fish adviser with the group size, substrate details, and recent changes in hand. Do not let a wasting fish ride to the next weekly entry. Holding the dated run of corydoras notes in KinsLe's Pet Passport gives that adviser the full story of barbels, behaviour, and water in one place.