I am having touble with the calibration of my hygrometers. I have a larger one from Radio Shack that has the outside probe (which I am not using). I have the little square Springfield one from Walmart. I started over with the process when someone told me I was using too much water. I was using 1/2 cup of water and salt. The larger one came up to 74-76%. The smaller one was about 8% off. So last night at 6:30 I clean up and started again with 1/2 cup salt and just 1/4 cup of water. This morning neither of them have gotten to 75%. Why? I know New England is dry this time of year. It is only about 30% humidity in my house. What do i do next? My shipped eggs should be arriving this week.