Water quality testers are devices used to measure various parameters of water, such as pH, turbidity, and the presence of contaminants. These testers help ensure that water is safe for drinking, swimming, and other uses. They can be handheld or part of larger systems, making them suitable for both personal and professional use. Many water quality testers utilize sensors to provide real-time data, allowing users to quickly assess water conditions. Some models are designed for specific environments, such as aquariums or swimming pools, while others are versatile enough for drinking water or environmental monitoring.