Just tested today. The hanna read exactly at 3ppm. I wasnt sure tgat the readings were accurate because the day before i dosed some nitrates (nyos) because the nitrate checker said that my nitrates where at 0.9. I tested nitrates on my salifert kit and it read 25 ppm. I was wondering if anyone else has issues like this with their checkers and if anyone has a solution. Thanks in advance

