Question
Robyn,

I have 9000ltr pond that did suffer from green water, however, I installed a uv and the water is now clear.  My goldfish (about 30) over wintered well and started feeding when spring arrived with plenty of activity all day long, Overnight about 3 days ago, they went to the bottom of the pond (about
6 feet)hid in some deep water plants and have not surfaced again for any reason, not even to feed. I have no idea why this has happened, any clues.

Pete

Answer
My guess would be that they are scared following a visit from a predator, most likely a heron.  Provide lots of cover for them, and they will eventually come back up.  In my case, I had to net the pond all the time after the herons decided it was their diner. With a 6' deep area, your fish can easily go down there to get away from most predators.  Otherwise, they would only go down if it got cold all of a sudden.  It doesn't sound like they're sick.

Robyn
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