Tetra Carbon Filters for Aquariums, Fits Whisper EX Filters, Cleans Aquarium Water, 4 Count

REPLACEMENT CARBON FILTER: Keeps aquarium water crystal clear, healthy and polished – activated carbon removes odors and discoloration. CATCHES DEBRIS: Layers of multi-density floss effectively trap even the smallest particulates. FOR TETRA WHISPER EX POWER FILTERS: Available in medium and large sizes to fit the range of Tetra Whisper EX Filters. CONVENIENT: Replacement filter cartridges are fully assembled and ready to use. USAGE: Change monthly or sooner if needed.