The Xiaomi Smart Pet Fountain Filter Set is a great way to breathe new life into your Xiaomi Smart Pet Fountain. The filter set includes everything you need for the maintenance of your pet fountain, including two main filters, two pre-filter units, and a water pipe. The four-stage, efficient deep filtration system can remove impurities such as fine particles, hair, and residual chlorine, as well as Ca or Mg ions that can cause kidney stones. These contaminants are effectively captured and filtered, ensuring healthy, tasty water that pets love to drink. It is recommended to replace the filter and filter unit once a month for better filtering results. Pair the Xiaomi Smart Pet Fountain with the Mi Home/Xiaomi Home app to receive timely reminders for filter changes.