4" Filter Sock

100 micron polypropylene felt provides the best solution for aquarium filtration. Made from durable and washable 100 micron polypropylene felt.

When should I replace my filter bags? This depends on the size of your aquarium and the amount of livestock you have present. You can be the best judge of your own aquarium. Being made from felt material they are easily reusable after washing in a standard home clothes washing machine. We recommend replacing them after 20-30 wash cycles