I purchased my tank used, was used by previous owner for SW. I didn't think to ask at the time if he had ever used copper in the tank. The tank is still cycling now but I've read that if copper was ever used it will kill inverts and I would like eventually to have some snails and crabs. I am using his bio-wheel. Should I be concerned? Do I just add a few inverts (when the time is right) and see what happens or can I test the water for copper? Thanks, Kat.
