This is super! I love the effect of the water. Thank you for taking us step by step through the set up. Could you tell me what PU foam is and is the plaster - ordinary wall plaster or plaster of paris?When Junior made a space landscape he did it with paper mache and it took ages to dry, does this foam and plaster mix dry quickly? Where have you set up the diorama?Elaine
Great display and thanks for the step by step. Here in the US it's common to use extruded polystyrene sheets for diorama bases. It can be found at hardware stores and is the pink board used for insulation. Some paper mache or plaster is recommended if you want to spray paint it - the spray paint will melt it otherwise.