Waterfalls

I'm changing the spillway to the garden again but am not finished yet. It is still almost what the last photo shows, with more of the rocks cemented in place. The main reason for that is because Camron walks on them and the channel is starting to collapse (I wouldn't tell him not to, it's his yard - I just need to fix it so he can), but also, that area was created without any kind of plan - just the thought that water flows downhill, and it needs some kind of finishing done to it along with the childproofing. Other than supplying water for the fish and plants, my main interest in the waterways are the sounds. I change the larger waterfall often, sometimes everyday, to change the sounds, and my favorite so far is water falling on thin pieces of slate then into a small pool of water. A better sound is also what I want from the part that I am working on now. While writing this I've realized some other things that I should have also done by this point, but so far I've stabilized the larger rocks, filled in the holes between the rocks and bricks, and made two small collection areas right before the channel turns toward the garden. Still no plan, that just seemed like the thing to do to get the sound I am wanting.