How the BRITA MEMO works To ensure an optimum performance you should change your cartridge on a regular base. The BRITA “MEMO” as featured for example on Fjord. Atlantis. Aluna and Cool is the world’s first electronic cartridge exchange indicator.The easy to use button counts down the remaining cartridge life. “MEMO’s” flashing display tells you to change your cartridge. MEMO Start Each time you fit a new cartridge. press the “START” button until the indicator shows 100%. MEMO Count The “MEMO” feature will then count down the remaining cartridge life. MEMO Change The flashing display tells you when to change the cartridge.