I have brookies in my pond that I like to grill and smoke, so I avoid any chemical additives. The copper will settle to the bottom, killing the phytoplankton on the way and eventually, all the beneficial bacteria and organisms on the bottom.
I agree with Bill, it will take a lot, or a lot of time. Depending upon pH and alkalinity, sooner for some, longer for others.
If you feed your fish, you aren't as dependent on a healthy ecosystem as I am but those bacteria on the bottom you kill, are also good for reducing pond muck and the development of a healthy food chain.
It's a slippery slope when you start adding any chemical to your water. One problem is solved by one chemical leading to another issue remedied by another chemical, ad nauseam.
You're best served by mitigating the issue causing the need.
