Jupiter Science has used a proprietary matting between the Venus cell electrodes. With any water ionizer, it is essential that this material allow water to pass during ionization. What can happen, however, is that, unless there is an automatic cleaning cycle, very hard water will leave deposits on this material and eventually lower its transfer efficiency. The new proprietary matting used in the Venus water cell is extremely resistant to mineral deposits. Lime, iron, and other minerals are "sloughed off" enabling better ionization for a long period of time. Comes with a limited lifetime warranty and free shipping!