Terrariums look great initially but are not always functional! Succulents and cactus need drainage and air circulation! If your terrarium is enclosed and gets condensation/water on the glass, it’s NO GOOD for your succulents. It will rot them! Remove the top or make sure there is an open side at all times! If there is no drainage, use rocks/gravel on bottom to hold excess water. DO NOT water if you can see water on the bottom!!!