I have always had difficulty getting CYA to easily dissolve. I have done socks in the skimmer but that messed up my ph probe readings. I did socks attached to my return jet, but that had to be often repeated. I finally used the liquified CYA last year, but that was unpleasantly expensive.
This year I used a small bucket, added dry CYA to the bottom, filled it toward the top with warm water and blended thoroughly with a hand held food mixer similar this one:

After blending for a while I poured the liquid off the top through a fine strainer and repeated a few times always leaving the sludge in the bottom and returnig what the strainer held to the bucket. Whatever sludge was left the first day I left in warm water overnight and repeated the next day.
In 72 H my CYA went from unreadable to just over 30 PPM where I keep it. This was the fastest I have had with dry CYA.
Hope this helps someone.
This year I used a small bucket, added dry CYA to the bottom, filled it toward the top with warm water and blended thoroughly with a hand held food mixer similar this one:

After blending for a while I poured the liquid off the top through a fine strainer and repeated a few times always leaving the sludge in the bottom and returnig what the strainer held to the bucket. Whatever sludge was left the first day I left in warm water overnight and repeated the next day.
In 72 H my CYA went from unreadable to just over 30 PPM where I keep it. This was the fastest I have had with dry CYA.
Hope this helps someone.