Kishu Charcoal X-Large is the ideal way to ensure plenty of delicious Kishu filtered water for all your cooking and drinking needs. Ideally used in any 3-5 gallon jug, Kishu begins working immediately bonding with toxins. Optimal filtration time is 48 hours. Kishu is simply left in the vessel until it's time to renew - we recommend once per month - simply place in a shallow pan of water, boil gently 5 minutes, dry out for 20 minutes. Enjoy the taste of natural spring water with Kishu Charcoal. One stick lasts 4 months.