So far I have siliconed the back of what is going to be the water feature. I've done this to make the outside look a little nicer and it's something the greatstuff will stick to better. As you can see in the pictures I have also started to greatstuff the water feature. The silicon was put on fairly thick so that took at least two weeks to cure. There is no longer a vinegar smell.
This is what it looked like the next day after we added a little more greatstuff and let it cure. I'm going to add more layers tonight. That will be the concave section of the waterfall. It's still got a little more work and more greatstuff but I'm pleased so far with the outcome.
