The HI782 Marine Nitrate High Range Colorimeter is specifically designed to quickly and accurately determine high levels of nitrate for saltwater aquariums and marine applications. With a digital read out, there is no more struggling to determine colors...

Get accurate water testing results with the HI781 Marine Nitrate Low Range Colorimeter. With a digital read out, there is no more struggling to determine colors visually. This nitrate tester's compact design fits in your pocket or stores easily in...