Answer: Regarding the ALFILTRA FCA 30 deacidification system and the calcite refill requirement: Over the course of use, the amount of calcite, which serves as the main medium for water deacidification, will gradually decrease. This is a normal process caused by the continuous neutralization of the acid in the water. Instead of a complete replacement, only regular replenishment of the calcite is required to maintain the system's effective function. This filling can easily be done by purchasing calcite in bags from us as accessories. It is important to note that the frequency of refills depends on various factors, including the water quality and water usage in your home or business. We recommend checking calcite levels regularly and refilling as necessary to ensure continuous and efficient deacidification of your water.