I'm in the process of having a pool installed and the crew just finished the rock waterfall. The waterfall was not built to specs but our builder claims he has already used the six tons we purchased. The tallest point on the waterfall was suppose to be about 3'6" but is actually 26". Can anyone tell me if this is six tons of rock? I have seen several and it doesn't appear to me that it is, but I may be wrong. I know it's difficult to estimate from a picture, but just as a reference the spa is raised 12". the highest point is 26", and the total lenght is ~9 to 10'. It's moss rock. Thanks.

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