A filter assembly (106, 600) for separating microcarriers from a fluid medium and cells, the filter assembly comprising: a container comprising a flexible bag bounding a sterile compartment adapted to hold a fluid; an inlet port (151, 604) through which fluid comprising microcarriers, fluid medium, and cells flows into the compartment; an outlet port through which fluid comprising fluid medium and cells flows out of the compartment; and a filter (170, 602) disposed within the compartment and bounding an inlet chamber (204, 622), the filter dividing the compartment into the inlet chamber (204, 622) that is fluidly coupled with the inlet port and an outlet chamber that is fluidly coupled with the outlet port, characterized in that the filter allowing the fluid medium and the cells to pass therethrough but preventing the microcarriers disposed in the fluid medium from passing therethrough, the filter comprising a filter inlet port communicating with the inlet chamber (204, 622) and a dip tube line extending between the filter inlet port and the inlet port (151, 604), wherein the filter (170, 602) comprises: a plurality of sheets (618, 620), at least one of the sheets being comprised of a porous material, the plurality of sheets being bounded together at their peripheries to form the inlet chamber (204, 622); and the filter inlet port through which fluid flows into the inlet chamber, the filter inlet port extending through at least one of the plurality of sheets, the filter inlet port being fluidly coupled with the inlet port (151, 604). a container comprising a flexible bag bounding a sterile compartment adapted to hold a fluid; an inlet port (151, 604) through which fluid comprising microcarriers, fluid medium, and cells flows into the compartment; an outlet port through which fluid comprising fluid medium and cells flows out of the compartment; and a filter (170, 602) disposed within the compartment and bounding an inlet chamber (204, 622), the filter dividing the compartment into the inlet chamber (204, 622) that is fluidly coupled with the inlet port and an outlet chamber that is fluidly coupled with the outlet port, characterized in that the filter allowing the fluid medium and the cells to pass therethrough but preventing the microcarriers disposed in the fluid medium from passing therethrough, the filter comprising a filter inlet port communicating with the inlet chamber (204, 622) and a dip tube line extending between the filter inlet port and the inlet port (151, 604), wherein the filter (170, 602) comprises: a plurality of sheets (618, 620), at least one of the sheets being comprised of a porous material, the plurality of sheets being bounded together at their peripheries to form the inlet chamber (204, 622); and the filter inlet port through which fluid flows into the inlet chamber, the filter inlet port extending through at least one of the plurality of sheets, the filter inlet port being fluidly coupled with the inlet port (151, 604). a plurality of sheets (618, 620), at least one of the sheets being comprised of a porous material, the plurality of sheets being bounded together at their peripheries to form the inlet chamber (204, 622); and the filter inlet port through which fluid flows into the inlet chamber, the filter inlet port extending through at least one of the plurality of sheets, the filter inlet port being fluidly coupled with the inlet port (151, 604).