You can force your test kit to test higher by taking one part pool water, mixed one part distilled water, mixing well, running the test, then multiplying your result x 2. If it still isn't reading high enough, use one part pool water and 2 parts distilled, test, then multiply x 3. (This is referred to around the forum as Carld's shotglass method! ). You'll lose a little accuracy with each dilution, but it'll get you in the ballpark.

If it was clear, and is now cloudy, Watermom's right, you need to shock the pool up to 15 ppm and keep it there until it clears and there's no overnight chlorine loss.

Janet