That is a good possibility. The more plants the more evapotranspiration, and higher humidity. And open top aquariums are like humidity trays.wilbeck said:I'll mist with RO or DH water a bit more now after getting this advice. Thanks. Perhaps I need to get a hygrometer for the solarium, though the room does have other houseplants and an aquarium in it, so maybe that's all I need to maintain a fair level of humidity.