I have a small 6 x 9 pond. Last year I had 5 fish (4 comet and 1 Shubunkin). Last summer we had babies, so the number was up to probably 11 or 12. In the winter I shut off the stream and add a tank deicer to keep the water open.
The problem for the past couple of years is that the fish seem to make it through the harsh winter fine. But when spring cleanout comes, I'm always missing a few. When the melting starts and water starts to go brown from runoff, I can't keep count of them, so I never know when they are missing. This year I added a grid of PVC and fishing line to deter any predators, though I have never seen any predators or tracks of predators.
I have just found the shubunkin floating. Thus begins my overwinter loss of fish. I'm wondering if the runoff and decay is too much for them. Perhaps I should start filtering earlier. I usually start the pump mid march to get the water cleared, though I bypass the stream and underground hose so I don't break it (ahem, as I did one year).
So does anyone have any ideas of what is going on?