well i finally made the piece of crap get on the 7.01 calibration mode, and switched from 7.01 solution to 4.01 solution. The reason why mines a pos is it takes forever to stabalize, it will keep going up or down and sometimes it gives false readings. I've seen it show 7.5 on 6.5 water and after putting it in the 7.0 solution, and getting a steady 6.95-7.2 out of it, it will show 6.5 in the water, right where my test strips are showing. I think its fairly acurate but it needs to stay in the 7.0 solution before testing water.