i have a swg installed 4-week ago and its not making any chlorine.. i was told because of my nitrate is to high (65 ppm) my swg will not work...i have a inground 16x36 3ft by 5.5 deep. about 22,000 gal of water. the place i purchase it said to drain 30in of water add it back, i did and the nitrate reading still was 65 ppm.. any help out there!!!!!!!!!!!!