Features 1、Establish stable soft water, reduce PH fluctuations, is a breeding auxiliary filter for straw tank and weak acid freshwater fish. 2、With the circulating water, the calcium, magnesium, sodium, potassium, and various cations resulting in hard water were exchanged,make the water soft. 3、Made of pure natural resin material, it is non-toxic and can be renewable used. 4、Suitable for water tank and weak acid freshwater tank. 5、Fast to improve and purify the water quality. Specifications: Condition: 100% Brand New Item Type: Resin Filter Material Material: Resin Color: As Pictures Shown Weight: Approx. 309g Shape: particle Function: make water quality appears soft water condition Regeneration method: 1. Rinse the soft water resin with tap water, add 100g of salt to 1kg of tap water, and soak the resin in an aqueous solution of salt for 30-60 minutes, until the resin returns to its original brown color. 2. Rinse under running water for 5-10 minutes to remove the salt. Package List 1x Resin Filter Material