Portable Water Quality Testing: Ideal for environmental science studies, this turbidity tube is perfect for assessing water clarity in homeschools, classrooms, and professional labs. A comprehensive instruction guide in included. Simple Operation: Measure turbidity effortlessly by filling the tube, draining until the Secchi disk is visible, and recording the water level for accurate results. Durable Design: With a length of 25.5 inches and a diameter of 2 inches, this tube is built for repeated use in various educational and professional settings. Versatile Educational Tool: Perfect for hands-on learning, demonstrations, and fieldwork, making it a go-to resource in any environmental science curriculum. Professional-Grade Accuracy: Trusted by educators and scientists alike for reliable water quality monitoring, especially in areas without advanced instruments. Turbidity is the measurement of the cloudiness of a fluid. To measure turbidity using this apparatus, fill the tube with water and drain it slowly by limiting flow with the pinch clamp on the hose. Stop draining once the black and white Secchi disk on the bottom of the tube becomes visible, and then take note of the water level using the graduations on the tube. The length of the tube is 25.5 inches and the diameter is 2 inches.