A way that I increase humidity in my germination station is first I place a heat mat down, then I place a 10x20 tray (1020) over the heat mat and put about a half inch of water in it. I then place another smaller tray in the middle of the 1020 tray and place my seedlings on the tray. (It ends up looking like a seedling island. The heat from the mat will keep the seedlings warm and the water will slowly evaporate raising the humidity in the small tent to 70 to 75% from 46%. Make sure you use a heat mat with a thermostat and or thermal probe.