Thanks, Jan.

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Glad to know I don't have to drain the pond.

I did get an Oase PondoVac, which I am trying to get to work right,
but it's being a tempermental pain in the neck. In the meantime, I
know I have to be careful about fines and hydrogen sulfide gas, so I'm
net-cleaning the bottom just a little at a time, so I don't stir too
much up at once. I do have a good filter that I think will trap much
of the stirred up fines, and also a UV sterilizer.

Okay, I guess you've convinced me though. I'll have to start doing
small water changes.

Fortunately, I live in Pacific Northwest like you, where we get plenty
of rain in the fall, winter, and spring, and the pond has a nice
overflow, so I think we've been getting some water exchange that way.

Joan
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