BUWUSMU 7.87 Inch Plastic Secchi Disk Set – Secchi Disc with Black and White Quadrants, Steel Cone, Holding Line, and 30 Meter Tape Measure for Clarity Measurements

Comprehensive Package: Each set includes all the necessary items for water clarity measurements. The package contains 1 Secchi disk, 1 roll of holding string, 1 cone weight, and 1 tape measure. This ensures you have the essential tools for accurately measuring water transparency in both fresh and seawater.
Ideal Size: The Secchi disc, with a diameter of approximately 7.87 inches (20 cm), is well-sized for efficient visibility underwater. The tape measure features a length of about 30 meters(only meter measurement), and the rope is approximately 16.4 ft (5 meters) long. These measurements provide ample depth tolerance for deep water clarity measurement without hindrance.
Quality Materials: The acrylic Secchi disc, a crucial component, is made from acrylic, ensuring resilience, lightweight portability, and durability. The cone, designed to weigh down the disc, is crafted from stainless steel for longevity and resistance to rust. The holding string is made from robust polymer, capable of handling the disc and cone weight without elasticity, making it sturdy for long-term use.
Freshwater Measuring: Use the black and white side of the disc. On an unclouded day with stable water surface, lower the acrylic Secchi disc into the water with a holding rope until it is hardly visible from above. Measure the length of the rope immersed in water, repeat several times, and calculate the average for freshwater clarity.
Saltwater Measuring: Use the pure white side of the disc. At the backlight of the main deck, put the plastic Secchi disc into the water, sinking to a depth just out of sight. Slowly lift the rope until the disc is faintly visible. Read the mark of the rope on the water surface, repeat 2 or 3 times, and calculate the average for observed clarity. In wavy conditions, correct the depth if the inclination angle exceeds 15 degrees, and read the marks at the crest and trough respectively.
Notice: The Tape Measure is only meter measurement. Please confirm it is suitable for you before buying.