Infinite Cauldrons

Toss Kelp into a Cauldron to prevent it from running out of water.

As of 1.20.5, I'm no longer updating this. The reason for this: You can easily waterlog nearby blocks as a water source. Examples: Waterlog a line of 3 stairs behind the cauldron with the flat sides twoards the caudlron so it doesn't spill out, or waterlog 3 upper-planks in the floor front of the cauldron.