Our high-density durable premium aquarium filter sponge pads are constructed with several layers of polyester fibres capturing large and fine particles. The filter pads are up to 5cm thick and can be cut to size to suit any aquarium filter or sump. Our aquarium filter sponge pads are fluorescent dye-free which is commonly used to enhance the whiteness of polyester fibres. Key Features and Important Notes: High-density design to aid in crystal clear water. Cut to size aquarium filter material. Traps uneaten food, waste, detritus and floating particulates from the water. Made from aquatic-safe 100% high-quality polyester fibres. Free from ultraviolet and disperse dyes.  We manufacture all our own filter media and sponges to ensure the highest performance and quality. Do you use a shocking amount of filter pads? If so drop us a message we can provide larger sizes and a little discount on bulk orders.