Started pool late wednesday afternoon.So far it's went from a green/black color to mid-green color with the shallow becoming milky in this short time, i checked cya yesterday and couldn't get a reading with the tube filled to overflowing (tft test kit of course). Should i add cya now or wait till i've got the pool clear?? I'm basing my shock level on 20ppm cya since i didnt get a reading at all,plus going couple of points above the level recommended by the chart. I'm checking chlorine level every 3 to 4 hours and adjusting as needed. Backwashing at every opportunity,we're having numerous showers today and tomorrow.