I am dealing with the same issue but at a larger scale, If I had only one cham I would seal the edges of the bottom with aquarium caulking, drill holes in the bottom below the ficus that would be raised on pedestal and drain into a bucket. I have to drain 15 plus cages so I am building a drainage system with a pvc frame, thick black plastic sheets that funnel into drainage line that connect to all my cages then lead into a main waste reservoir. I will post pics when it's complete as well as plans. I want to make something easy and cost effective for all of us cham fanatics.