I just had my Walmart above ground pool filled today. The company didn't bring enough water (that always seems to happen) so I had to fill the rest with our WV (very hard) well water. I only had to add about 15% well water. Once I added the chlorine (please don't ask how much ) the water turned green by the time I was back in the house. How can I get it clear again? This is our second year and I am still clueless. Thanks!