Investigations of Different Filters for Biological Water Treatment in Swimming and Bathing Ponds

Abstract

Swimming and bathing enjoys a high status as a sport and recreational activity and is generally regarded as healthpromoting. The demand for swimming ponds, which recycle water without chlorine, is increasing worldwide. Previously used filters for biological water treatment in swimming and bathing ponds are very complex, because of their multilayered structure. On the basis of comparative tests it could be proven that simplified filter structures lead to equal or even better cleaning performances. Furthermore, it could be shown that the gravel layer at the filter inlet is not only of particular importance regarding a uniform water distribution, but also plays a key role regarding the microbiological activity.