We have a new pool with a chlorine generator and the company that closed the pool last year (we live in the northeast) used a copper containing algecide.A few days after the pool was reopened a yellow-brown stain appeared on the fiberglass steps and all the plastic water jets. The chlorine generator manufacture said it was copper stains from the algecide. My questions are: how can we remove the stains and is there anyway of stopping them from coming back, short of completely emptying the pool?