Sheer Descent waterfalls should have a minimum of 12 GPM, per foot to achieve a 1 foot projection. The more flow from a pump, will produce a further projection.

So for example, (2) 6' units equal 12 feet. They would require 144 GPM. Proper pipe size has to be calculated to properly deliver the water at that rate. Then, the proper pump can matched based on those requirements. Your builder will have to do some math.

We always have individual pumps for separate water features. Not only does it allow you to run them separately, but also allows those features to be properly matched with pipe and pump sizing for proper results.

Our spas have a 2 pump system whereas the jets have their own pump and the filtration pump is for heating and treating. We NEVER use the filtration pump for the jets.