Marineland Canister Filter C-160 & C-220 Filter Foam, Rite-Size S BULK TWELVE PACK BULK PACKAGING: For this version we remove the Pads from the bulky packaging and pass on the shipping savings with a lower product price Rite-Size S Replacement Filter Foam for Marineland C-Series C-160 & C-220 Canister Filters Marineland Filter Foam should be cleaned and rinsed every three weeks and replaced every nine weeks. Do not clean with soaps or abrasives. Rinse thoroughly before use. Each of the SIX PACKS contain two pads (12 pads total)