A submersible pump, comprising: a casing, having accommodated therein a pumping unit and a drive unit for driving the pumping unit; a base, defining a pump inlet; and a float control unit. The float control unit comprises: a float, having at least one magnet; and a float chamber housing, defining a float chamber in which the float is movable up and down. The float chamber has at least one opening which connects the float chamber with an external environment. At least part of the float chamber housing is movably or removably attached to an outer wall of a casing of the submersible pump.