On Wed, 19 Sep 2012 10:04:09 EDT, Jason C wrote:

Are you thinking of the big pond spilling too heavily in to the smaller pon
d, making it overflow?

That was my concern, too. But if it works out like I'm thinking, then both
ponds would basically be stand-alone ponds, and the only overflow from the
big one would come from the water pumped from the smaller one. So, if I pum
p 500gph out, then it would bring 500gph back in.

In theory, anyway! I haven't started the project yet, though, so I'm very m
uch open to discussion on that.

One needs to take into account the spill over water, at what point,
gallon-wise, does it stop spilling over when the pump is off? Can the
smaller pond handle the extra water? If not, you'd want to make plans for
it to flow over somewhere without carrying soil/plants away, etc.

Best is usually small pond, large pond for those of us that don't want
spill over when the power goes out or during maintenance.

My top pond is ~ 500 gallons, bottom pond ~ 800, and that flows into a
bio-filter of ~ 200 gallons. The biofilter lip was made a tad higher than
the lower pond edge so flow over is out of the lower pond, though I do have
a flow over I can use out of the filter. Usually cap that during the season
and use it during the winter for water changes. HTHs, ~ jan

------------
Zone 7a, SE Washington State
Ponds: www.jjspond.us