We installed an intex above ground pool (48" by 15') at the end of last year with a sand pump and salt water system. The water has remained crystal clear since September and still remains crystal clear. Whenever I test the water, it never shows any chlorine in the water. Why would this be? I am confused because I know the water wouldn't be crystal clear without the chlorine but at the same time I want to make sure the water is safe for my kids to swim in. Any help would be appreciated.