A device and method for cleaning a water environment of sludge, comprising a chamber connected to a supply channel and a driving module. A supply channel (3) has a connector pipe outlet (32) in the upper zone (13) of the chamber (1), and the outlet (301) is located in this upper zone (13), and a sludge container (11) is in the lower part of the chamber (1) with impervious walls (12). A supply channel (3) and/or its outlet (32) is located inside the chamber (1) and/or tangentially to the chamber (1) wall (12). The device along with the chamber (1) and the supply channel (3) constitutes an integral part of aquarium or a replaceable module put into an aquarium. The chamber (1) is divided into compartments (120) set by vertical partitions (121).