What hygrometer are you using? They are notoriously inaccurate. I've been most successful with the nat geo hygro/thermometer so far. I usually have 2 in my tanks at all times to try to get the best idea of what is going on. So each of them have a nat geo and exo terra at the moment. The exo terras gives me a constant reading of 99% while nat geo seems to be more on.