What characterizes soft water in terms of calcium carbonate concentration?

Soft water is characterized by having a lower concentration of calcium carbonate (CaCO3) in its composition, which influences its overall hardness. Typically, water is classified as soft when the concentration of CaCO3 is less than 50 parts per million (ppm). This classification is significant in aquatic environments, as lower concentrations of calcium and magnesium ions, which contribute to water hardness, can affect aquatic life, the solubility of minerals, and the behavior of pesticides.

Water with less than 50 ppm CaCO3 ensures a certain level of softness, making it more effective in certain applications such as agriculture and horticulture, where the presence of dissolved minerals can impact growth and soil conditions. Understanding the distinction between soft and hard water is essential for managing aquatic ecosystems and applying the correct pest control strategies.