The Grohe Blue cleaning cartridge keeps your Grohe Blue system clean and fully functional, delivering great-tasting and refreshing water. For optimal cleaning power, use the specially designed Grohe adapter. The cleaning agent guarantees 100% natural disinfection and is safe for humans. The empty bottle can also be recycled. The Grohe Blue cleaning cartridge ensures pure water at all times. Please note that the cleaning cartridge cannot be used without the adapter.