Dimensions: 12" x 23" x 2"; 30 PPI pre-filter foam sponges - Provides both mechanical and biological filtration: effectively capture large debris while supporting beneficial bacteria, helping to keep water clear and healthy. - Low clogging design: built to resist rapid clogging, reducing maintenance frequency. - Cut to fit: can be trimmed to match your filter dimensions for a precise fit. - Wide compatibility: suitable for any aquarium or pool filter. - Safe for aquatic life: Bio Sponge Filter Media Pad is dye-free and safe for fish and other aquatic pets. - Freshwater or saltwater ready: suitable for both freshwater and marine setups. - Durable and reusable: designed for regular cleaning and reuse, offering long-term value. 2-3 practical use scenarios - Use in external canister or hang-on-back filters: replace or augment existing pre-filter media by cutting to the required shape and size. - Custom fit for non-standard filter chambers: trim to fit unusual or tight spaces in sump or filter boxes to maintain effective filtration. - Primary or supplementary bio-mechanical media: provide ongoing mechanical filtration while supporting biological filtration in both freshwater and saltwater tanks. Notes - Suitable for any aquarium or pool filter, and designed for repeated cleaning and reuse without loss of performance. - Safe for aquatic life and produced without dyes.