Aarke Purifier is a patented water filter jug in glass and stainless steel. Our water filter pitcher makes your tap water cleaner and more pleasurable to drink. The filtering technology is developed in collaboration with BWT and features a refillable steel filter cartridge and filter refill granules. The granules are poured into the cartridge and changed every 4 weeks. Two filter refill granules options are available: Pure and Enriched. Scroll down to view which contaminants they reduce.