It depends on the quantity and quality of water that passes through the filter. The higher the degree of contamination and its use, the lower the lifespan of the cartridge. In metropolitan areas, the cartridge usually lasts around 6 months. To maintain the cartridge proper functioning you should: - Do preventive maintenance, evaluating the quantity and the quality of the water to be purified. - Clean the cartridges with your bare hands or with a new soft sponge. - Do not use any chemicals to clean the cartridge. When cleaning the cartridge with water do not turn it upside down so no contaminated water gets inside. - Do not use excessive force to clean it as their base can detach. - Write down the day the cartridge was installed for you to know when to make the replacement (every 500L or 6 months of use).