Winter precautions
Question:
I have a 35×37 foot koi and goldfish pond that is 3-4 feet deep. This is my first winter as a pond owner. I have 3 saucer pond de-icers. I have lost several fish so far, mostly the largest fish. I thought I have taken every precaution to prevent winter kill but obviously not. What could I have done wrong? I have a bog filtration system and the pumps are off now. I also fed them the fall fish food in prep for the winter. I stopped feeding them when the water temperature was appropriate. They don’t act oxygen deprived. Help!
Answer:
The problem may be that the Koi find enough natural food to produce more waste than the bog filter can handle this time of year or that there is oxygen deprivation.
Test the pond water for ammonia and nitrite. If that is the problem then a large dose of large pond/lake beneficial bacteria may help alleviate the problem.
If no ammonia and/or nitrite is present then it is most likely oxygen deprivation and a large air pump will alleviate the problem. Our hunch is that it is this latter problem.