Purdue ADDL if you want to waste your time and money. There won't be any sense of urgency on their part and by the time they get back to you your problem will be long over with. Sorry, telling you like it is from personal experience as one that has had fish tested and being involved in the aquaculture field.
Sounds like acute copper poisoning that was sprayed directly on winter stressed fish. Stop spraying and your deaths should subside.
Are you using a chelated copper?
Most problems with fish are due to stress caused directly or indirectly by the pond owner, whether it be too much and too large an area applied of herbicides, too many fish and or improper stocking and/or planting the wrong kind of fish and the problems that come with that, preventable pond turn overs, etc. We are our own worst enemy at times myself included. Many of us have become fairly skilled pond managers by making mistakes or learning from the mistakes of others.
Last edited by Cecil Baird1; 04/01/13 09:40 AM.
