I arrived at my 3 acre pond the other day and noticed several floating white masses. Went out on my floating dock to discover there were 20-30 dead bass and a couple grass carp. It was only the largest of fish that died. I saw no small fish. Went out again today and didn’t notice any more, so I think it was a one or two day time that they all died in. I also saw the elusive white koi that has to be 20 lbs or so, that I’ve seen lurking the last few seasons, and it was alive and swimming.

We had a HUGE downpour a week before I noticed the kill, where my pond rose about 4 feet in one night. The water turned brownish, but has since gone back to its normal green color.

I have aerators running 24/7 that have been in for four years.

Any ideas on what I should look at to figure out what caused this? I’m four years into owning this pond and was really unhappy to see the largest of my bass floating around dead.

Thanks!