You can run humidity as high as 85% without a problem as long as you keep the tank very clean. If the tank is not scrupulously clean, mold fungus, scale rot, and other issues can become problematic. My humidity swings from 65%-85% ambient, with a few spots at 99-100%. My BP will often spend days in her Humid hide. When I take her out she has water droplets on her. It is much easier to keep your tank humidity in the 60-70 range and provide a few damp hides.

David