Rebuild after a new cartridge is actually installed
Illustrative inputs, not verified product specifications or care recommendations.The household question
A replacement has a fresh capacity count and installation date.

Measurements and assumptions
Before the change
| Rated capacity (litres) | 600 |
|---|---|
| Litres already used | 500 |
| Litres used per day | 5 |
| Installation date | 2026-01-01 |
| Date of current usage count | 2026-02-01 |
| Manufacturer maximum calendar life (days) | 180 |
| Item name | Rebuild after a new cartridge is actually installed |
| Storage location | Household supply shelf |
| Minimum stock | 0 |
After the change
| Rated capacity (litres) | 600 |
|---|---|
| Litres already used | 0 |
| Litres used per day | 5 |
| Installation date | 2026-02-21 |
| Date of current usage count | 2026-02-21 |
| Manufacturer maximum calendar life (days) | 180 |
| Item name | Rebuild after a new cartridge is actually installed |
| Storage location | Household supply shelf |
| Minimum stock | 0 |
Carry out this task
- Create or open the Before record on the linked tool.
- Save the genuine replacement event and then rebuild.
- Check the saved After values before downloading the rebuilt label. Replace the older physical label.
Calculation and observed tool result
Before
Capacity remaining = max(0, 600 − 500) = 100 litres; 100 ÷ 5 = 20 days. Calendar limit 2026-06-30; earlier estimated review 2026-02-21 (20 days from count date).Recorded quantity: 100 litres.
After
Capacity remaining = max(0, 600 − 0) = 600 litres; 600 ÷ 5 = 120 days. Calendar limit 2026-08-20; earlier estimated review 2026-06-21 (120 days from count date).Recorded quantity: 600 litres.
What the result means
The new record starts with 600 litres of entered capacity.
Limits of this example
The software cannot verify that a replacement physically occurred.
A mistake to avoid
Resetting usage without replacing the cartridge would erase its history.
Open Water Filter Cartridge Life Calculator · How to Keep QR Inventory Labels Accurate