Each Fractal Water Vortex Magnetic System array is tested for leaks at 80 PSI, magnetic strength and vorticity (how the water is spun). Fractal Water offers a full 10 year warranty against defects and magnetic strength. Your Vortex Magnetic System is designed to provide to you years of trouble free service. However, over time, magnets lose their strength, our magnets are specially shielded to reduce magnetic flux loss over time. Our magnets should last you for 30 years, though we only warranty for 10 years. If for any reason your magnetic flux is lost within that 10 year period, we will replace the magnets. Please contact us for any questions regarding how to test the magnetic strength of your unit.