Evolution Aqua K1 Filter MediaEvolution Aqua K1 Filter Media Proven Moving Bed Filtration Technology K1 Filter Media is Evolution Aquas award winning filtration solution, designed to deliver exceptional biological and mechanical filtration in both moving and static bed systems. Used exclusively in the Nexus and EazyPod filter systems, K1 Media has become a trusted standard in koi and pond filtration over the last two decades. With a protected surface area of 500m per m, K1