I hope people don't get tired of me suggesting this, as I have done for about 5 other posters. But try this. Get a warm mist humidifier (one that boils the water) put it next to the tank and funnel all the steam over to the top of the cage. I use aluminum foil. I am able to keep my humidity as high as I want this way. It also helps boost temps since the steam is warm. Works for me in my 40 gallon glass tank.
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