Do you have a lot of plants? Some can be very thirsty, or divert water
outside the pond with their leaves. It sounds like a lot in three days
to me. I would look for water splashing out or (hopefully not) a leak
somewhere.
"rtk" wrote in message ...
We're finally getting some rain-free days and even enough sun to cause
more evaporation than I would have expected. One hundred gallons in
three days from two ponds whose surface areas together are less than
150
square feet. Does that seem suspiciously high and perhaps caused by
something other than normal loss.

Ruth Kazez