Write the Autopsy While the Tank Is Still Empty
A breakdown reset usually begins in a rush — livestock into buckets, substrate out, glass scrubbed — and by the time the tank is refilled, the details that explain the failure have literally gone down the drain. Capture them first. Before you strip anything, photograph the tank as it stood: algae patterns, plant melt, the state of the substrate surface, where detritus collected. Note the last test results you took and the symptoms in the order you noticed them — the cloudiness that came before the deaths, the gasping that followed the water change. This failure timeline is the document's spine; everything else hangs off it, and it cannot be reconstructed honestly a week later.
Record What the Livestock Went Through
Make a plain list of who was in the tank when it failed and what happened to each group: who survived, who died, who went to a hospital tank or a friend's setup, and in what condition. Include the recent arrivals and anything new added in the weeks before — a plant, a rock, a second-hand filter — because breakdowns so often trace back to an innocent-looking addition. Record any treatments you tried during the decline and whether they seemed to help, harm or do nothing. This is not about blame; it is the evidence any future investigation stands on, and it is exactly the detail that memory quietly edits out.
Log the Reset as a New Tank With a Past
Give the rebuilt tank its own setup record rather than continuing the old log as if nothing happened: substrate chosen and why, which equipment was kept, cleaned out or replaced, what water the cycle was started with and how the cycle was fed and tested. Link the two records with a single line in each — the new log points back to the breakdown file, and the old one ends with a note that the tank was reset and why. Treating the reset as a new beginning with a documented past stops the classic error of judging the new tank against a rosy memory of the old one's best month.
Turn the Failure Into a Changed Habit
A breakdown document that changes nothing is just an archive of regret. Close it with the two or three specific changes the failure bought: the test you will now run weekly because the drift went unnoticed, the quarantine step that is no longer optional because a new fish carried something in, the maintenance task moved from monthly to fortnightly because the filter was silently clogged. Write them as rules in the new tank's log, not as intentions in the breakdown file. When the same temptation appears — skipping the test, rushing the acclimation — the written rule argues back.
Keep the File Where the Next Decision Happens
Store the breakdown record with the new tank's log, not in a separate archive you will never open: the next time you consider a risky stocking addition or a major rescape, the failure notes should be one reach away. If the tank is ever sold, given away or handed to a sitter for a long stretch, the record travels with it — an honest history makes you a more credible keeper and the next owner a better-informed one. That habit of keeping the file with the fish is what KinsLe's Pet Passport is built around: the tank's breakdown, reset and running records kept together in one portable packet, ready whenever a vet visit, a move or a handover needs the whole story.