The all new HI 700 Checker Ammonia LR for fresh water can be used in place of HI 3824 or HI 38049 fresh water test kits. The CheckerHC is a simple, accurate, and cost effective way to measure low ranges of ammonia in fresh water. Designed as a more accurate alternative to chemical test kits, the HI 700 provides quick, accurate results in four easy steps. 1.) Step One - Add a sample to the included cuvette(s) 2.) Step Two - Insert sample into the Checker and zero it out 3.) Step Three - Remove sample and add reagent (A & B - 4 drops of each) 4.) Step Four - Reinsert sample and click the button to measure your results or... - Press and hold the button for 3 seconds for a time reaction reading The HI 700 uses an adaptation of the ASTM Manual of Water and Environmental Technology, D1426-92, Nessler method. The reaction between ammonia and reagents causes a yellow tint in the sample. FEATURES/BENEFITS: * Small palm-sized design * Accurate from ±0.05ppm ± 5% of reading * Dedicated to a single parameter * Uses a single AAA battery * Auto Power Off after 10 minutes in inactivity * Built-in timer for timed reaction readings PRIMARY APPLICATIONS: * Water Quality * Education * Freshwater Aquariums * Wastewater * Environmental HI700 COMES WITH: The HI 700 CheckerHC is supplied with a reagent starter kit (1 bottle of 700A-0 reagent A and 1 bottle of 700B-0 reagent B), 1 x 1.5V AAA battery and an instruction manual. Included is (2) HI 700-25 (50 reagents)