I have operated my swimming pool with minimal problems for nearly 7 years. This year, I did the same process I always do in opening my pool (after winterization). I added the necessary chemicals and balanced the water. As usual, the water turned from algae green to blue. However, the water never cleared. I added an extra bottle of clarifier, but it did nothing. I have been able to hypothesize that my problem is the filter. When I backwash the filter, it is spitting out clear water. However, there is only about 2 feet of clarity in my pool. I opened up my filter and everything seems to be fine. What am I missing?