When the cartridge need to be replaced, this signal blinking a week ago in advance. After a week, the device will be stopped automatically. It is designed for 90 days limitation because the performance and efficacy can be reduced. For this reason, cartridge should be replaced as soon as possible.
The cartridge shelf time is one year and it is vaild for 3 months after open it. Therefore purchasing two cartridges is recommended when the second cartridge is replaced. Please keep the cartridge in a cool place or refrigerator.
The cartridge is used for 3 months and the device stops automatically after 3 months regardless of the remaining amount. Check the cartridge replacement signal and replace it. Since the cartridge liquid is sensitive to temperature and humidity especially in summer and it provided in sufficient amount , so even after 3 months, the remaining cartridge must be discarded and replaced with a new cartridge. After 3 months, deterioration of the liquid can cause problems to normal device performance.