Aquarium filter sponge,polyurethane foam materials .Reticulated, open cell(10ppi--70ppi) colorful,:eg:blue,white,black,yellow ... Aquarium filter sponge , polyurethane foam materials .Reticulated and open cell, widely used for water treatment , aquarium , cooling tower ... ....We manufacture foam sheet, block and other any shapes .Open cell, the pore size from fine to coarse . Aquarium filter ...