Hi Bill,

The dredging part is fine. Any muck that is stirred up is sucked up by the hose, and the pond should stay fairly clean.

Complications arise when you start running out of pond water. Usually, the dredged water is returned to the main body, and is really soupy. Of course that would kill most of your fish. If the water can be collected and settled for a couple of days, it shouldn't harm the fish. The devil is in the details, as they say.

If you could do the dredging in steps so that none of the nasty water was returned to the pond, that would be ideal.

Shrimp