haha.. fragile?? hahaha.. when I siphon the tank I actually heave myself up the right short side and step into it.. the structure is 21mm (almost a full inch) ply with 160 plugs that are drilled in a 30 degree angle " \ / " and about 30 high performance screws for maximum stability.. if, and I'm really saying if, it breaks it would be in the seams.. I could have gone with external bracing but since I deamed it unnecessary since I overdimensioned everything from the start.