Depth filtration is one of the most efficient and economical types of filtrations and is often used in the biotechnology industry as the first step after cultivation of cells. In this process, the cells are often cultivated at high cell densities (HCD) so that they produce a specific target molecule. Depending on the cell types chosen, they may need further processing before harvest, such as lysis. Subsequently, the cells and cell fragments respectively, are to be removed using various processes so that the subsequent chromatography steps can be performed. However, these high cell densities and the different upstream process steps pose a major challenge in the subsequent downstream process. Here we show that with the help of a filter aid and the right choice of filter media, a significantly higher filter capacity can be achieved. By adding a filter aid to the unfiltered cell culture, a filter cake is formed on top of the filter layer, which leads to an increased filtration capacity. Based on the cell suspension to be filtered, different filter aids, and mixtures thereof, can be added. In addition to the maximized capacity, turbidity is also significantly reduced, so that chromatography or sterile filtration can be performed directly if necessary. This reduces the number of purification steps in the downstream process, which in turn saves time.