From the large Aquaculture industry to the home hobbyist, Bio-Bale is the filter medium of choice for professionals. Simple in concept, Bio-Bale owes its extreme effectiveness to its high surface area versus volume and its unique surface texture. With 250 square feet of surface area per cubic foot and 33 square feet per gallon, Bio-Bale cannot be matched. Bio-Bale is produced from one continuous piece of F.D.A. approved, non-toxic plastic designed specifically for CPR. Bio-Bale is measured precisely by computer to achieve a consistent surface area.