Abstract: The present invention relates to a filtration apparatus composed of: a container comprising a central well and a number of radial individual chambers, each of said chambers comprising: a filtration bed placed on a plate, said plate defining with the bottom of the container an evacuation chamber; an open gullet admitting the water, and an aperture situated towards the top end of the well and connecting said chamber with said well, each well being equipped at its base with a discharge pipe and said container comprising at its base a discharge pipe for the pure water.