You can use activated carbon to take the copper out of your system if you havent already (thats why the directions on the coppersafe say to remove any activated carbon while using it). The frequent water changes that youve mostelikely been doing will have already replaced what water you wer at one time dosing. Witch means you have already physicaly removed the copper. Copper should be long gone by now via water changes alone.
The only problem you would face is: did you have any lace rock in your system? If so you might want to take it out of your system. I have read that lacerock can actually hold stuff like copper in it and release it at later times.
If you dont know what lacerock is you probably dont have any. (its the really cheap rocks you see at your LFS usually sitting around on shelves and in bins, greyish, rough and extremely porous, mostly used for freshwater tanks) sometimes people buy it because its so cheap and will eventually become "live" if in their systems long enough.
Other then that if your still scared run some activated carbon in your system for a bit and do a big water change. But, like I said before as long as youve been on your water changes its already gone. hope that helped.