Here's what I do (for what it's worth). Set the sluice up. After you notice alot of black sand build-up, put a 5 gal bucket at the discharge end of the sluice. Now, starting at the top-most riffle, dislodge the sand using your fingers. Working down to the last riffle, collect the sand in the bucket for panning later. You can keep this up for long periods. Then, the final clean-up goes into the same bucket you've been using to collect the sand in. In other words, no need to shut the sluice down till you're ready for final clean-up. TTC