I am not sure I am in the right place, but I'll give it a try.
I am building a pond/waterfall. The purpose is to have a large waterfall. The pond will be clear water. No fish or plants. It's really a large fountain.
The waterfall will be 7 feet wide annd have three drops. The pond will hold about 800 gallons. (8 ft x 6 ft x 2 ft)
By my calculations, I will need a pump in the 10,000 GPH range.
Would you use an internal or external pump?
What would be more efficient?
Any comments are appreciated.
I am adding a drawing of the fountain.