The answer is the fountain nozzle on the top.

Yes, it really does make all the difference. The height of the stone is about 50 % of the diameter of the catchment area in which it sits,  Nothing wrong with that.

But to "add interest" some one has added a fountain nozzle, this fountain nozzle projected water above the height of the rock, which in turn breaks the J.W. Rule

Not to mention the small diameter of the jets can easily get blocked with grit / dust from the display

The makers of this only intended water to run down the faces of the stone. Which is why you can not see the fountain jet, because the sump is almost empty

It would seem some one has been reading this page, the nozzle has been removed, here is what it should look like

Fountain errors Index

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