Water flowing, pouring, trickling
Water flowing and pouring from one small basin into a bucket.
Drop height is a half meter. The stream is finger thick at first and then diminishes to be a mere trickle.
It starts with the first gush into the empty bucket.
Then the calm flow onto the calm surface of water.
Then the flow gets perturbed and loud.
Then it gets less and less until only a few drops are hitting the surface.
Add some reverb and you got a rivulet in a cave.
Add another reverb and you have a good bathtub situation.