Aqueon Carbon Reducer for QuietFlow Specialty Filter Pads provide additional filtration to remove specific contaminants from your aquarium. The Carbon pads remove pollutants and organic debris that discolor water, improving water clarity and reducing odor. Improving water clarity and reduces odor Fits the Quiet Flow LED Pro 10 Pre-cut for easy installation For QuietFlow LED Pro Power Filters Replace pad every 2-3 weeks for optimal filtration.