As opposed to regular up-to-down flows of fixed bed, floating-bed systems operate, regenerate and backwash in the direction of bottom-to-top. Small particle-sized resins compacted on the upper layer are easy to float up with the up-flowing water, potentially blocking water caps or strainers.

EPS-FB inert polymers are designed to be filled right under the top device and above the resin layers. With their large granularity and light density, they attach to the cap or strainer for complete protection. This prevents rapid drops in operating pressure and ensures uniform distribution of liquids.