Bead question

The hygro is a dial type that came with it, but when i did the salt test it sat right on 74% so i figured it was good. I just bought a digital hygro and am in the process of salt testing it.

The rh in the basement where i keep them is in the 50s. The outside rh is about 68% today.. I live in east Tn so the humidity is always pretty high in the summer.

Is it possible to over moisten the beads? The humi is only a couple hundred cubic inches big and i have heartfelt 65rh for up to 540cui.