Clearing the Clouds

[kk]

I've done it all. Balanced, shocked, clarified (twice), algaecided (copper based), diluted, cleaned sand then even changed sand. Pool store says no chemical reason water is still cloudy. There was finally a little clearing after sand change. Twenty years of pool keeping and I've never had water that wouldn't clear but I got hurt at end of season last year and pool turned to swampwater. It's an 18K gallon 27 round with sand filter. If copper algaecide is possibly excessive and causing cloudiness, how do I dilute or remove it? Pool store is riduculous, they suggested 30 bags of shock. Any suggestions are appreciated. kck@servisupport.com