A system including an enclosure of a washing machine, a drum within the enclosure, a mixing unit, within the enclosure but separate from the drum and in fluid communication with the drum, a water supply unit coupled to the mixing unit, a reservoir having a conduit fluidly coupled to the mixing unit, and a container connecting assembly configured to fix a spout of a container to the reservoir. An apparatus including a reservoir, external to a washing machine, to receive a liquid wash aid, a container connecting assembly coupled to the reservoir and configured to fix a spout of a container containing liquid wash aid to the reservoir, a flexible conduit to pass liquid wash aid from the reservoir to the washing machine, and a wash aid control unit connected to the flexible conduit and adapted to meter a flow of liquid wash aid from the reservoir to the washing machine.