The red nose is your first record entry
A rummy-nose tetra file should open with colour, because the deep red nose and striped tail of a settled, healthy fish fade visibly when water or stress is wrong. On day one, photograph the shoal close to the glass, note how many arrived, their source, and whether the red is bright, patchy, or washed out after the journey. Record any individual whose nose stays pale in the following week or who schools apart from the group. That simple colour baseline turns a famous indicator into evidence: a later pale morning can be compared with dated photos rather than argued from memory.
Warm, soft, stable: the water log this shoal needs
Rummy-nose tetras favour warm, soft, slightly acidic water and dislike swings, so log temperature and pH at every test alongside ammonia, nitrite, and nitrate, and note hardness if you measure it. Record how you prepare change water and whether its temperature and chemistry are matched before it goes in, because this species often reacts to the change itself rather than the tank's steady state. Write down each water change with before-and-after readings for the first two months. A pattern of pale noses the morning after every change points at preparation, and only a written sequence reveals it.
Schooling and spacing behaviour to track
Note how the rummy-nose shoal actually uses the tank: tight schooling along the length, loose grazing among plants, or huddling near the heater or filter. Record tank length in the setup section, since this active swimmer needs horizontal space, and list tank mates with a line on any chasing or fin-nipping the tetras receive. Add dated notes when the shoal splits, when one fish hovers alone, or when the group startles persistently at room movement. For a fish this sensitive, behaviour changes often precede visible symptoms, and dated behaviour lines are frequently the earliest useful thing you can hand an aquatic vet.
Feeding records for small, mid-water mouths
Log the size and type of food offered, because rummy-nose tetras take small food in mid-water and lose out when larger tank mates monopolise the surface. Note whether the whole shoal feeds, whether crushed or micro food improved the response, and any fish that repeatedly mouths and rejects food. Record colour alongside feeding: a shoal whose noses redden within an hour of a good meal is giving you a repeatable wellbeing check. Keep holiday feeding instructions in this section too, naming who fed the shoal and what, so a pale, overfed, or underfed week after a trip can be read in context.
One sensitive shoal, one complete file
Keep the colour photos, water log, and behaviour notes together and backed up, with the equipment list — heater reliability matters for this species — and the quarantine steps used for any later additions to the shoal. Update the count the day it changes, and note the source of every top-up group so different batches are not blurred into one history. When the file is complete, a new keeper inherits not just fish but the exact conditions under which they glowed. Filing those tetra records in KinsLe through a Pet Passport keeps the records together in one portable packet for any vet visit, move, or handover.