Your apparatus looks really great, you are well on the way to making a lot of hydrogen, use your kit with the regulated power supply and either salt water or water with a little battery acid added and watch the hydrogen bubble. Remember though that you will get a lot of hydrogen from your apparatus and this is explosive if mixed with air, it wants to go back to being water again!!! A small amount mixeds with air will give you a really loud pop like you hear in the video, if you accidentally quarter fill a room with it you will create an explosion that will blow the windows out, your apparatus could easily make that much gas.
Also remember the act of switching on your power supply generates a little spark in the switch that could ignite the gas when you were not expecting it to if it has escaped into the room, be careful and have lots of fun.
Hydrogen is comletely colorless, odourless and burns hotter and a lot faster than gasoline, the space shuttle runs on liquid hydrogen as its main fuel, even NASA got that wrong once.
Bob.