Originally Posted by pitrack
Is that what you would typically run for a 24" tall rock with a 1" hole? I personally have only done installs with 2" holes and use larger pumps (2500-3000gph per hole) so I'm not familiar with 1" holes. Just curious.
Do you happen to have any pictures of them?
The size of the piping was not given in the opening post, nor was the type of rock or width.
For a 24" high bubbler, I would use 1/2" piping. You are not trying to create a waterfall or a geyser, but, at 24" height, a subtle feature with some ambient background noise IMO. If building a larger feature that is intended to be the focal point in the landscape, everything is increased proportionately.
Aquascape recommends, for example, 3/4" piping with an 800 gph pump on all of their single basalt columns up to 3' height and 3/4" piping and a 2000 gph pump on their sets of three basalt columns or about 667 gph per column. With 1/2" piping you can get the same effect with a 300 gph pump using less water and electricity.
It's really a question of what is the final effect that you are trying to achieve and how much impact you want the feature to make.