When opening my pool last weekend, I added D.E. to my filter through the skimmer. However, I think that the D.E. ended up in my pool. The pressure on my filter is 4 psi and didn't rise at all when the D.E. was added, but the pool became cloudy. So I waited a little while then decided to backwash the filter, but the water was clear the whole time. Then, I decided to open up the filter and found no D.E. at all in it. I did a cursory inspection but didn't find any rips or tears on the inside. So, I put it back together and turned the filter back on, and the pressure is still 4. Any ideas why the filter isn't accepting the D.E.? Any help would be appreciated.
The pool is 20,000 gallons and the filter is 60 sq. ft.