In this picture you can see how smoothly the water flows across the box.

This picture will give you an idea of just how fast the water is flowing. 

Notice the eddy below my hand.  And the waves above.

With some practice you will get the hang of it.  If the Water runs too fast.  It will not allow the gold and black sand to hang on the sluice box.  However if it runs too slow, the riffles will clog up.  Allowing the gold and black sand to travel over the riffles and off the back of the sluice box.

As I said, with some practice you will find a certain way you like for the combination to work for you. 

If the box is slow, increase the volume of water, or drop the back end some.

If it is too fast, set a large rock in front of the box to slow the water down, or raise the back end.  Or you can raise the front end some.

If the trail of material is all on one side of the box.  Turn it in the water so the water flows straight.  Or if this is not the problem, dump the material in the center of the box, not the side.


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