IVO Water Purifier Filter Cartridge Value Pack 1 units per Box Made In Japan 1500 liters per filter capacity No need for water delivery The lifespan of the cartridge would depend on the consumption, number of users, water quality and pressure so we do not normally provide an exact time estimate. But assuming that there are 3-5 members in the household using 15 liters a day, the faucet-mounted cartridge could last for 3 months. For a better comparison, the cartridge has an estimated lifespan of up to 1500 liters. This translates to 79pcs. of 5-gallon containers from water delivery. You'll know when to replace the cartridge when you can no longer tolerate the water flow. After some time, the flow rate would gradually decrease because the filter accumulates contaminants. But IVO is 99.99% bacteria-free until the very last drop!