In the past few days, I have been creating a waterfall paludarium, intended for African Reed Frogs, and possibly also African dwarf frogs, and cherry shrimp. The tank before setup. I used a 6 inch black pipe (not sure exactly what kind, found it in my garage ) to house the pump, hose and power cord, and wooden blocks to boost the flat rock ledges. This first layer of spray foam was just to keep everything in place. I next added the second layer of spray foam, which covered up the pipe and wood blocks. I also added a mopani log I had in store, and glued some gravel onto the backdrop to add texture. I siliconed it to the glass, and attached it to the spray foam, to make sure it stayed in place. I was able to flip it over, and get a preview of what it will look like.