Japanese Filter Mat   Ultra Media   TetraPond Biofilters   Filter Brushes Filter brush is an excellent mechanical and biological filter media, hangs vertically in pre-filter chamber to filter the solids before biological chamber 4 inch diameter.     Item  Description  Price   Order  FM/B24  Filter Brush 24"  (4" x 24" Diameter x Length) $5.50   Call for quantity discount FM/B12  Filter Brush 12"  (4" x 12" Diameter x Length)  $4.00   Call for quantity discount