can any one please help
i have just tested my tds meter (about 1 month old) with the soution and it read 258 my solution is 342 so i then tried it with my new tds meter that i have just opened and it also reads 258/260 i have not contaminated the solution with any other water any ideas as i am lost . my ro water is 2 on both meters and my washing water is 000 so why is this plus my solution is brand new just out of packet i also had a tds that i just could not calibrate it would not go on to 342 how ever many time i tried so it went back plus i dont want to try and calibrate the meters as i dont want it to go wrong again please help thanks stu