Abstract: An aerator for liquids, particularly an aerator for water, includes at least one aerating basin and a plurality of immersible elongate bodies, which are contained in said basin and secured to the peripheries of wheels, which revolve about an axis that is parallel to the surface of the liquid in the aerating basin. As a result, each immersible body emerges entirely out of the liquid on one side of the aerating basin and is entirely immersed into said liquid on the other side of the basin. Each immersible body comprises a plurality of axially aligned discs, which have webs provided at their rim with a peripherally and axially extending edge flange so that a chamber is defined between adjacent discs. Each edge flange is formed with a slot in a portion which faces downwardly as it enters the liquid.