Fixed bed for aerobic or anaerobic wastewater purification

Fixed bed for aerobic or anaerobic wastewater purification, at least comprising a first frame (1) having a first support element (6) having opposite side rails (2, 3) and/or intermediate rails (4) capable of fastening textile supports for microorganisms, a second frame (5) having a second support element (6) capable of fixing the textile supports to the second frame and means connecting the first and second frames (1, 5) at least in a corner region of the first and second frames, characterised in that the first and second frames (1, 5) are provided with spacers (7, 8) at least in the corner regions, the height of said spacers corresponding to the height of the textile supports as fastened between two frames (1, 5), where the textile supports are fixed to the side rails (2, 3) and/or intermediate rails (4) of the first and second frames by means of the first and second support elements (6), in that the means are one of lateral mounting elements (10) or columns (11), the columns insertable into through-bearings in or on the spacers (7, 8), and in that the frames can be assembled by joining the lateral mounting elements (10) or by inserting long columns (11) into the through-bearings, and the fixed bed can be inserted into a wastewater tank.