Question: what are ppm and ppt?
Answer: ppm = parts per million ppt = parts per thousand. 1 ppm = 0.001 ppt. 1 ppt = 1000 ppm. A meter that reads 0 to 10,000 ppm is the equivalent of a meter that reads from 0 to 10.00 ppt. A reading of 5000 ppm is equal to a reading of 5.00 ppt.