I have had an API test kit in my storage which is now 5 years old. I have ~150 gallons of water and according to the online calculator I dosed 10% ammonia chloride (ACE hardware) of 17ml. I waited about half an hour and checked with the old test kit. I don't have another ammonia test kit only a Salifert basic reef test kit: Nitrate, Phosphate, Ph, KH, CA, Mg. I don't plan to buy an Ammonia kit no need. I was trying to conduct a digestion test. The Ammonia test shows a change in color indicating that the reagents aren't inactive but the color is in the blue spectrum.