Aquis Advance 550/750 Sponge Pad - 15ppi Blue (2pk) 401s AquaOne Replacement Media advance aquis 550/750 foam blue 15ppi. AquaOne coarse filter pads are designed especially to remove the larger particles of dirt and grime from your aquarium. The coarse filter pad is made of high quality pored foam, allowing only water which has been cleared of larger particles to pass through the pad. The coarse filter pad will serve as a biological and mechanical filter, which is essential in keeping your aquarium healthy.
Not only are the AquaOne coarse filter pads re-usable (Rinse and reuse again and again) but they also last longer than your fine wool filter pad making the AquaOne coarse filter pads very low maintenance. Please note once your pad loses shape it will need replacing, failure to do so will lead to particles avoiding the filter process. It is easy to install and has 2 per pack.