Ok..so I bought a Hanna checker for mag..got it yesterday in mail so tested water 1st test said 1800ppm said no way so did another test maybe I did something wrong 2nd test was 1600..then did a salifert test said 1250 an did that twice same 1250..so these a.m. did the Hanna test again 1st test was blinking 1800 so that mean it higher then that said to myself no way did another said 1750. So did the salifert test again an it's 1250 again so idk what is goin on anyone else have these problem..I mean I followed the instructions to a t.