"RichToyBox" wrote in message
news:RayUa.133935$OZ2.26262@rwcrnsc54...
Your filter system design, sounds like the one BV put in. It is a very
good
design. Do a Google for BV pond design.
snip

Summary: Bottom drain in pond runs uphill and empties into VF. Pipe if below
water level, so VF is gravity fed. Pump sits in VF at far end from feed
pipe. This pump pushes water back to the pond. I have only cleaned by pump's
intake once so far this year. The bottom, is no more dirty then any area of
my pond so far, with only a 1/4 inch or so of algae/clay. Also keep in mind,
I have not yet installed my diffuser, so my bottom drain is just a 4'' pipe
sticking up about 2 inches from the bottom of the pond.

BV.