A filter aid composition may include an acid-treated composite silicate. The composite silicate comprises a silicate substrate and a precipitated silica. A method for making a filter aid composition may include providing a silicate substrate, precipitating a silica onto the silicate substrate to form a composite silicate, and treating the composite silicate with an acid to form an acid-treated composite silicate. A method for filtering a non-aqueous liquid may include providing a non-aqueous liquid for filtering and filtering the non-aqueous liquid through an acid-treated composite silicate. The composite silicate may include a silicate substrate and a precipitated silica. A filter aid may include an acid-treated composite diatomite. The acid-treated composite diatomite may include a diatomite substrate and a precipitated silica gel coating. The precipitated silica may be a precipitated ilica gel.