Filter balls for sand filter system without sand deposits, eco-friendly filter balls for sand filter system Clear and happy swimming pool water, comfortable swimming time in hot summer Advantages Spherical Filter Pump Media: 1 . Perfect replacement for filtering sand, clearer pool water 2. Quickly filter pool impurities, continuously fresh pool water 3. Cool and environmentally friendly materials, which can exert the best filtering performance of the sand filter system 4. Can be machine washed and reused, environmental protection and low cost 5. Widely used in all sand filter systems. Suitable for all existing sand filter systems such as swimming pools, aquariums, filter pumps, aquariums Product parameters: Alternative effect: Filter ball 1.5 lbs = 50 lbs of pool sand 3 lbs filter ball = 100 lbs of pool sand