Can't get bubble column

[YellowGreenCraft]

So those elevators on the creative server had water blocks placed all the way up? The one at my fishing farm was created by building the tower and the placing one water block at the top.

There is a simple trick to it, make your column, ad a water source on top of it then grow a kelp in it, when the kelp grows the falling water will change into a source block.

Good luck