If you added pool care shock to your pool with hard water and it turned a brownish color how can you fix it?

I added a copper-based algecide to our pool. Then 12 hours later, I shocked to pool. Our pool water turned a chocolate brown. What happended was the algecide was copper-based, and the copper reacted with the chlorine in the shock... and turned brown. We had to wait for the chlorine level to significantly drop, then add metal remover. Let the water circulate until clear. Then re-shock to get the chlorine levels up. If you wait to shock the pool too long, your water will then turn blue (ours did!).