Many pond builders have found that adding a bottom drain helps keep a pond cleaner.  Fish waste and other much that accumulates in a pond can be easily removed by a bottom drain.  Ponds that are over 2' deep can become stagnant without a bottom drain. 

The bottom drain is installed under the liner.  Flex PVC pipe carries the water under the liner to the skimmer box.  A bulkhead fitting is installed in the skimmer.  A PVC male adapter connects the flex PVC to the bulkhead fitting.  A valve is placed inside the skimmer box to control flow.  When the pump is turned on, water will flow into the skimmer through the skimmer faceplate (surface water) as well as the bottom drain.  You can control how much water goes in through the top / bottom inlets with the valve on the bottom drain.  Bottom drain kits include EBD bottom drain pictured above, bulkhead fitting, valve and fittings. 2" kit recommended for PS1 skimmers, 3" for PS2 skimmers.  Does not include PVC pipe.

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