HDPE Geomembrane Fish Farming Pond Tarpaulin Liner . The HDPE Geomembrane is made of 97.5% polyethylene virgin resin, 2.5% carbonblack, antiaging agent, antioxidant,ultraviolet HENAN OKAYorber, stabilizer and other additives,by internationally advanced multiple Layer extrusion blow molding process or multihead flat extrusion process.