Mineral cartridge systems are sold under the following trademarked names: Jandy Nature 2, Vision and FROG. These products kill contaminants, primarily bacteria, in the water as it passes through a cartridge. This means the pump and filter must run for long periods of time to treat the tens of thousands of gallons of water in a swimming pool. Pool suppliers, who sell these systems, often recommend that you run your pump and filter 24 hours per day, 7 days per week.
In some cases more than one cartridge may be needed in one season. There is no obvious way to determine when these cartridges fail to be effective. Their effectiveness may expire prior to the cartridge contents being totally depleted.