Diatomaceous earth filter with base filtra- - tion facility

摘要

Water, e.g. contained in a swimming bath, is ducted via ports in the upper and lower regions of the bath to an upper communal channel debouching to the upper surface of a filter unit, pref. constructed in a diatomaceous material, the water is filtered to a lower outlet port under the action of gravity or an automatic pump. All levels in the bath are filtered and the treated water is recycled to the bath.