Okay filled her up with water today. I'll remineralize the water tomorrow. I didn't do it yet as I thought I might have to do a whole water change because of the new substrate. But it is surprisingly clean from my washing it in a pillowcase.
The tree however is a magic tree. So it started floating.
Well we couldn't have that, so I naturally put a rock on top of it until it decides to really put down its roots!
I was worried about your pile of substrate, but I saw your note on the rocks. That should help keep the hill in place. Another idea for a good hill or terrace is to stack pieces of eggcrate covered with screen and then just cover the assembly with a layer of substrate.