Like the others have said misting is a great option. Also still container of water under the dome will help keep it high as they are evaporating into the closed environment. Keeping the vest shut on the dome also helps. I don't find seed mats are needed for cannabis and can make things worse. I would try with out them first and see how it goes. I also love to add in some beneficial microbes into the medium to help it have a good defence against pathogenic ones.
Good Luck!
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