I am not a pro so take this with the proverbial grain of salt. FWIW Maybe it is at least partly explained by DO content of the water. Your neighbor is supplying his pond with high DO water after running thru the stream. If your geo is like mine, the water is piped directly from my well, thru the geo unit and then to the pond. Water as it comes from a well has near 0 dissolved O2. I have my winter diffuser located to keep open water over my geo discharge and the flow is directed across the diffuser in an effort to at least partially aerate it as it comes into the pond.

Edit: Your geo is also cooling your well water so you may be actually pumping colder water into your pond than your neighbor

Last edited by Bill D.; 02/23/15 07:45 PM.
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