Hanna Instruments HI781 Marine Nitrate Low Range Checker

The HI781 Marine Nitrate Low Range Colorimeter is designed to accurately determine low range nitrate levels in saltwater aquariums and marine applications. With a digital read out, there is no more struggling to determine colors visually.  Range: 0.00 to 5.00 ppm (as NO3–) [0.0 to 50.0 ppm (calculated) using dilution] Built-in timer so you don't miss a step. Saltwater Compatible