1. Sand in the pool does not cause cloudiness.

2. Sand *missing* from the filter DOES cause cloudiness.

3. Sand that is too coarse (anything other than labeled filter sand INCLUDING Quikrete 'filter sand') causes cloudiness.

4. Anything that ends up in the skimmer sock, when you stir the pool is NOT sand; sand sinks too fast.

Did you use some sort of zeolite or sand replacement media?

On what date did you first do the DE test?

Now that you can see a bit more in the pool, can you do the DE test again, with 4 cups of DE, and make sure that DE is not getting through your filter?