I checked the ingredients. The tabs have the trichloro chlorine and a zinc and 2% other ingredients. The algaecide has several hard to remember ingredients but none said copper. I don't have anymore of the shock to look at. When I was dealing with the pool store, they suggested metal magic. The pool guy that cares for pools said to use it along with another product to help filter much quicker. He said it would clog the filter pretty fast. We didn't buy either b/c by that point we felt we were being "had". They said even though we have city water they've seen it before. However with the fill last summer we did not have any metal problem. I don't know, but I've been battling this five or six weeks now. I'm tired of cleaning filters and brushing the pool. We've had murky almost brown to green to cloudy white/pale green to almost turquoise but always very cloudy, and now pretty green again. We have yet to see anywhere near the bottom. Is there any hope? I'm thinking just do well enough to get by until the fall, drain it and start over next year. Thanks.