My humidity stays at 80, no problem, I misted heavy for the first week until they found the water. And really only misted the glass for them to climb in. It never fogged up totaly, small fog spots would clear in an hour, water drops would evaporate in 1/2 a day.
Now that they've located the water, I'll probably only have to water the plants once a week to get humidity to rise again. I do have mold growing on a mushroom that wasn't dried enough, but vinager keeping that in check.