I have one of the cheapo wallyworld hygrometers. I recently upgraded my humidification system in my larger humi (thanks again scott) so I recalibrated my accu-rite hygrometer using the salt and water and storage bag method. Most examples suggest allowing the hygrometer to sit with the salt and water for about 8 hours and some suggest much longer. After about 12 hours my accu-rite was at about 67%, but then I let it sit much longer. After about 2.5-3 days it was at 75% and I concluded the test. My question is which reading was accurate. If allowed to sit for too long can the rh in the bag actually reach above 75%? I am concerned because after replacing it in my humi it is reading at 57%. If the first reading was accurate that means my humi is at 65%rh which is my target. If the second reading was accurate then I need to ad some moisture to the beads.

Thanks in advance.

By the way, the last time I calibrated the accu-rite it was at +1% (reached 74% during calibration)
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I would say 75% was the correct reading and that would be dead-on. When salt-testing, I always allow 48 hours to get a more accurate reading.
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i usually let sit for 48 hrs..to ge tht e acurate reading..75%
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Add more water to your beads. 75% of them should look wet and semi translucent.
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