Juwel poly pad is used to catch coarse particles of dirt in the water.. As a mechanical pre-filter, it protects the filter from rapid soiling and means that you don't have to clean the other filter media as often.. Juwel filter floss consists of fine, residue-free polyester material and is suitable for use in both saltwater and freshwater aquariums.. Features. Serves as a mechanical pre-filter. Protects other filter media from rapid soiling. Made of residue-free polyester material. Suitable for use in freshwater and saltwater aquariums. Instruction manuals. Change filter media. Compatibility chart