Aquarium Waterfall for powerhead

I want to create an aquarium sandfall/waterfall using a powerhead (not an air pump).
I take ispiration from this video where I've found a lot of DIY instrucions
https://www.youtube.com/watch?v=T2S00u1cjRg

So I've made 3 pieces to simplify my work.

The threaded piece must be inserted in the T joint
keep attention to direction, see the video below at minunte 1.36 for explanation
https://www.youtube.com/watch?v=Mdbtl8OF5Js
The thread, fit a soda bottle to use as a reservoir for sand, I