set the hidden attr is2d to "0"
fluidShape.is2d 0
then make the 3d container have depth resolution, it won't be great but it's all you can do. Also you are going to need the keep the resolution the same, so if you are at 100x100 now you will need to do something like 100x100x20 that will probably almost kill your machine but that's how you do it.