On Tue, 19 Aug 2003 15:47:30 +0100, "Iain Miller" wrote:

All well & good in theory but the problem I can see is in a couple of areas.
Firstly the pump chamber would need to be quite large

At least 50 gallons probably.

and secondly the
situation as to what happens in the event that there is a leak or a
significant loss of water through evaporation - the whole thing could just
stop working. It would seem to be very sensitive to the water level in the
pond(s).

The filter only need be a few inches higher than the lower pond sides.

So the question is as to whether this kind of system is worth pursuing & if
so how do you rig it to cater for variations in water level or do I just
chuck a submersible pump in the lower pond & pump upto a filter box at the
top end of the system?

See my website, 2 ponds similar to what you want to do, upper pond flows
into lower pond so a skimmer affect. When the pump is off the upper pond
only drops to the bottom of the spillway or 2-3 inches. Lower pond & filter
fill with excess. Lower pond has bottom drain and skimmer to filter. Pump
in pump chamber goes to top of stream/waterfall and empties into upper
pond. ~ jan See my ponds and filter design:

http://users.owt.com/jjspond/

~Keep 'em Wet!~
Tri-Cities WA Zone 7a
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