Introducing Aquatop?s 18?x10? Specialized Filtration Media Pad. This filter pad is made of a durable, rigid poly-fiber material and is uniquely enhanced to remove harmful toxins and organic particles from fresh or saltwater systems. The FP-1018PN is a special 2-in-1 Phosphate & Nitrate Removing Filter Pad that helps to prevent potential nuisance algae blooms by removing unwanted phosphates and nitrates from the water column for healthier, cleaner water. Made of a durable, rigid poly-fiber material Uniquely enhanced to remove harmful toxins and organic particles from fresh or saltwater systems prevents potential nuisance algae blooms by removing unwanted phosphates and nitrates from the water column for healthier, cleaner water

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