Aquarium filter floss, used in a wide range of filters on the market today, is key in helping you keep your filter free of even the finest and most stubborn aquarium particles. Big Al's Filter Floss is a high-quality solution for keeping your water crystal-clear no matter what and can be used in a wide range of aquarium applications. Ours is designed to be easy cut to fit your unique filter, so it suits a huge selection of filter systems. Because of this, our filter floss is also particularly useful in sump or custom-style filter systems. This floss is non-toxic, so you won't experience any discomfort or irritation when you handle it for long periods of time. Additionally, it is designed for safe use in both freshwater and marine aquariums.