Tourmaline balls for shrimp are rich in more than 30 elements and come in 5 regular and 5 large sizes. The regular size is 1 cm and the large size is 2 cm. Depending on the hardness of the water source, use one ball for every 2-5 gallons and one ball for every 5 gallons of the large size, and replace it approximately every 3 months. Provide your shrimp with more than 30 essential elements to promote activity, health, and vitality. These magic shrimp balls help the shrimp body shed color properly while strengthening the shell, thereby releasing these minerals into the environment. By improving water quality, it helps stabilize pH and provides a surface that helps reduce ammonia, nitrite, and nitrate levels, thereby promoting rapid plant growth. Plants also need minerals. Tourmaline balls help plant growth by adding essential elements to the aquarium. Suitable for all types of crustaceans, such as shrimp, crayfish and lobsters, as well as shelled invertebrates such as snails. Note: Rinse or soak before use.