Pure Aquatic Multi-Use Polyester filtration pads provide cost-effective media for a wide variety of filter types and models. Cut the 13 in. x 13 in. pads to the sizes or shapes needed to fit your filter for efficient removal of suspended particles and debris. Reusable pads can be rinsed clean and are perfect or use in aquarium filters, pond filters, sumps and more! Safe for use in both freshwater and saltwater, for all your mechanical filtration needs.