The Vitalizer Plus™ is equipped with a digital timer that records that amount of running time. After 4000 minutes (approx. 65 hours), “CC” will appear on the digital display, indicating that it is time to “Change the Cube.” For a single person making one batch (.6 gallons) of 9-minute water every day, the mineral cube will last well over 1 year (15 months). Greater use will precipitate the replacement of the mineral basket more frequently. After replacing the mineral basket, simultaneously hold down both the “minutes” and the “start/stop” button for 3-4 seconds, with the power button on. This will clear the digital timer and you will notice that “CL” replaces the “CC” – ready for another 4000 minutes of operation.