Aquarium Systems Mega Media Filter Wool is a synthetic filtration media designed for mechanical filtration in both freshwater and marine aquariums. Its unique fiber structure efficiently traps large and fine particles, improving water clarity and overall quality. The filter wool is compatible with internal filters, canister filters, and sump systems, and it does not affect water parameters, making it safe for all aquatic life. It can be rinsed and reused multiple times, providing an economical filtration solution. Available in fine, medium, and coarse grades, it comes in 500g packs suitable for various aquarium sizes.