Pet Information > ASK Experts > Pet Fish > Pond Water Gardening > over winter large koi in MN pond

over winter large koi in MN pond

25 9:50:54


my pond
My pond is 4000 gallons, 4 feet deep at the waterfall end. Surface size is approx 16' x 8'.I inherited this pond with the purchase of my house. This is my third winter. This winter there are many more fish, all sizes. 2 very large koi, each over 12"; 3 small 6' koi, severallarge gold fish and many smaller gold fish. I would guess there could be 100 fish in total in the pond. I have a deicer which I will start when the pond starts to freeze over. The pond man moved my pump with a pvc extension and it's spouting water, to keep the pond open and oxygen available. Because there are so many fish,are they at risk of dying? Do I need to feed the two very large koi? Thank you.

There is probably not a risk of dying because 4000 gallons is a good amount of water for 100 small fish with a few large ones.  Once they all get larger, you will probably come across a couple of Ammonia-related issues.  You do need to feed the larger koi until the water temperature is consistently below 55.