This is a multi-layer aquarium filter media kit designed for efficient mechanical, chemical, and biological filtration in freshwater or saltwater tanks. The set includes four identical filter cartridge assemblies, each comprising three distinct layers: a blue coarse sponge (pre-filter for debris), a white segmented pad with fine fiber and activated carbon sections (chemical filtration), and a black honeycomb bio-media ring (surface area for beneficial bacteria). Below the cartridges, raw filtration materials are displayed: orange-colored zeolite or ceramic granules (ammonia removal), cracked coconut shell (natural carbon source), black activated carbon granules (odor/toxin adsorption), and raw cotton balls (fine particulate trapping). The components are universal-fit, compatible with most hang-on-back (HOB) or canister filters. Ideal for maintaining water clarity, reducing nitrates, and supporting healthy microbial colonization. Suitable for hobbyist and intermediate aquarists seeking customizable, eco-friendly filtration solutions. Not branded—generic replacement media for standard filter housings.