Abstract: An apparatus for aerating water with fine bubbles is provided. At least one strip-like, inextensible aerating element is provided that has an air supply channel and there above a portion that is provided with slits which elastically widen under the effect of a supply of air. At least one holding element is secured to the base of a water reservoir that is to be aerated, wherein the aerating element is longitudinally displaceably held by the holding element such that with the reservoir filled, a pulling action on one end of the aerating element results in withdrawal thereof from the holding element.