Filter media often used in professional filters in aquaculture (trickle filters). Made of Polypropylene, which makes it absolutely safe for aquatic life, gives it a long life span and makes it easy to maintain. Surface area: 242m²/m³, mesh opening: 24mm. Large orders can be cut to size. Applications: cooling towers, gas washers, trickle filters, nitrification- Bio rotors, aquaculture.