The jukeboxes have a neck at the bottom of the tube that holds in little crystals... They keep the bubbles from coming up so large. If you can get small rocks at the bottom of that, it might help make more even smaller bubbles. A tiny aquarium pump would also have more power to it. Your diy pump is cool tho.
Anyone curious how you make a jukebox tube the old fashioned way... They used a solvent called methylene chloride. They use that because of its low boiling point. It's a chemical used in paint thinner but it itself isn't flammable luckily. 😂 You put that and a dye along with it (often amber colored). Then you'd sit the tube in a ceramic transistor very loosely and put metal shims to hold it in tightly. The transistor heated up and created the bubbles. The even bubbles came from a little neck at the bottom of the glass that held in little crystals.
