A filtering device includes a water pump, a filter cartridge, and a communicating tube for coupling the water pump with the filter cartridge. The filtering device further includes a flow switch attached to the communicating tube and configured to change switching states in response to a water flow rate in the communicating tube being lower than a predetermined value. The filtering device further includes a reminding device operably connected to the water flow switch. The reminding device generates a reminder signal when the state of the water flow indicates that the flow rate of the water in the communicating tube is lower than the predetermined value. The control system includes a control panel for the filtering pump, a central control system, and a filtration detecting system. The control panel is connected to the central control system and the central control system is connected to the filtration detecting system.