Please Help....

Am I doing something wrong???
I have continued to have 3" pucks in the skimmer and have gone through a 50# bucket, I buy at least 3 gal of bleach and add every night and I still have FC from 1-4 but CC is still 1.5 to 2.0 but what is real concerning to me is that I am doing something wrong is the pH.... I add box after box of Borax and still my pH is going down to 6.8.

Is there any advantage to "washing soda" over borax?
The only reason is that the Washing soda is cheaper where I live. I have only added Borax but I have added probably added at least 12-15 boxes since this started. (I just don't want to screw it up by adding too much, or maybe that is not possible)

Also I add the Borax through the skimmer, is there a better way???

(I don't know if this is an issue but I have a Poplar and Oak tree overhanging the pool as well as arborvitae shrubs about 10' from the pool. The Poplar trees have been releasing a long skinny "thing" when their leaves come out and collect in my skimmer, I dont know if that will effect the pH.)

My water is now clear without any real odor.

Thanks for your help

InGround Vinyl pool, 18x36, 22,000 gal, sand filter, heat pump, Live in PA, overhanging trees over the pool