A system for filtering spent grains from unfermented beer is disclosed. The system has a pot assembly having a stock pot wall, lid, drain tube and outlet valve. A louvered false bottom is positioned in the pot assembly and forms an opening between the false bottom and the stock pot wall. The louvered false bottom has a plurality of raised louvers spaced over the false bottom. Each of the louvers has a top surface, a bottom surface, a leg and a slot. The slot can be made larger or smaller according to the grain crush size.