Scottfarcuz, there has been an ongoing debate on the question of using a tank that was treated with copper. I can only go by my personal experience. As I said my 100 gallon reef which was set up in 1971 had copper in it many times. The quarintine tank that I have is many times used to hold corals that I am either giving away or for some reason keeping them apart is five gallons. In the 40 years or so that I have that tank there has been copper used in there many times. The last time was last week) The silicone is clear and I have no problems keeping corals or anemones in there. Malachite green or metheline blue will discolor anything and the only thing that will get that out is bleach. Copper is a very light blue and it is not a dye like metheline blue.
Also if you use copper in a tank at the proper dose which will be about one drop a gallon then empty the tank and rinse it there will theoretically be maybe a few drops of copper contaminated
water left in the space where the silicone meets the tank. If you then fill the tank with water thereby dilluting those few drops of copper contaminated water, there will still be many times less copper in there than there is in NSW. Copper is a trace element that fish and inverts need to survive. It is included in some salt mixes. We are not talking about toxic waste here. I ran my tank with tap water for years before they made small RO units and all of my house plumbing is copper, I know because I installed it.
If we are talking about copper contaminated coral rock that is a different story because that is porous and it absorbs copper but even that over years will disapate as it did in my reef. If you put copper contaminated rock in water the copper will gradually come out of the rock, it may take years for it all to be removed but eventually there will be no more copper in the rock. If the copper never comes out of the rock then whats the problem? As long as it's not in the water everything is fine. There is a theory that if the pH drops the copper will come out of the rock and contaminate your tank, I guess theoritically that could happen, but I wouldn't lose any sleep over it.
K-ROK, as I have been at this for fifty years I could tell you if a fish has ich from across the room. It is a good thing that you watch your fish closely as you should. I am sure you take very good care of your animals.
I am very informed about ich because when this hobby started almost all of our animals died from ich. Liquid copper was not readily available and test kits were unheard of neither was quarintining. Most people got out of the hobby almost before it got started. Now luckily my fish do not get ich and haven't had it in about 20 years but I used to get called many times to cure it in wholesalers or stores. The very best quickest cure is as I said quinicrine hydrocloride and copper.
Have a great day.
Paul
Copper doesen't seem to be affecting anything