I agree with Waste. Another thing that may be causing the slight cloudiness is the sequestering agent. You may need to shock the pool to get rid of the excess. It is only an opinion I have, and I don't know the science , but my experience is the same as yours - so I know exactly what you mean. My family think I am nuts too when I say the water isn't "sparkly" clear , but I know how I like it . What I did when the water got like that is to shock, and add a little acid to take the ph down to 7. Don't add any clarifier - I did that the first time, and it didn't help. The acid and shock seemed to do the trick. It took about a day for it to "sparkle" again. I don't know if it was that there was some algae, but my tests were the same as yours - no excess use of chlorine, and chlorine at a proper level at all times. So I don't know if it was the sequestering agent - because it did happen a couple of days after the sequestering agent went in, or if there was some algae forming. I just know that the water cleared up with some muriatic acid and taking the chlorine up to shock. Hope this helps, and I would be interested to see how your pool water turns out if you try this