Just wanted to pass on a tip to members and how to avoid making an easy mistake with Hanna Testers. When using the included syringe an easy mistake to make is taking it all the way to the top instead of to the "0" mark. (I made this mistake early on) Going all the way to the top of the syringe will give you (inaccurate)higher readings. Initially I assumed that all the way to the top was 1 ml but that is wrong. To the "0" is 1ml. Just passing on the tip.