The Aquabion S15 is a compact, 1/2-inch diameter water conditioner that provides limescale protection for small homes by transforming hard water minerals into a non-adhering form, preventing buildup in pipes and appliances. It operates without electricity, chemicals, or magnets, using zinc sacrificial anodes to create aragonite, a harmless form of calcium. The S15 is maintenance-free, offers up to seven years of protection, and does not add sodium to drinking water, making it a salt-free alternative to traditional water softeners. 
How it Works
Galvanic & Electrolytic Action: The system uses a galvanic and electrolytic solution to treat hard water minerals, particularly calcium.
Zinc Anodes: Zinc sacrificial anodes are housed within the unit.
Mineral Transformation: As hard water passes through the S15, the zinc reacts with calcium bicarbonate to form aragonite, a non-adhering, powdery form of lime.
Limescale Prevention: This transformation prevents the formation of hard, damaging limescale deposits on the interior surfaces of pipes and appliances. 
Key Features & Benefits
Compact Design: The 1/2-inch (DN15) size is ideal for smaller homes and apartments.
Salt-Free & Chemical-Free: It's a safe, eco-friendly option that doesn't increase sodium levels in drinking water or require chemical refills.
Maintenance-Free: Once installed, the unit requires no ongoing maintenance or salt top-ups.
Cost-Effective: The S15 can recoup its initial cost within a few years and provides up to seven years of limescale protection.
Proven Technology: The same technology is used in commercial settings like hotels and factories worldwide.
Easy Installation: The compact size allows for quick and easy integration into existing domestic plumbing. 
Important Considerations
Earth Bonding: The unit must be properly earthed for it to function correctly.
White Residue: You may see a harmless white powdery residue on fixtures; this is the aragonite and indicates the unit is working.
Lifespan: The zinc anodes deplete over time, and the unit will need replacement after approximately seven years, which will be signaled by a return of limescale.
Sizing: For a single shower at a time or a 15mm incoming mains, the S15 is the correct choice.