lotus® Water Treatment Replacement Carbon block filters offer a significant advantage over standard granular activated carbon filters. The particle size of the ground media and the force of compressed media in a block form, accurately control the pore size and flow rates. This means the chemical reductions and mechanical filtration can be accurately controlled and the increase in the carbon/water contact surface area provides a far greater life expectancy of the filter and improved filtration. For use only with the lotus® Water Treatment System.