New pool owner, trying to get my chemicals balanced

[mitchryan912]

3. Depending on how they tested, the testing error for CYA levels at the low end can range from plus-minus 10 ppm (K2006 with experienced user) to plus-minus 50 ppm (eye-balled test strips). I don't know your pool volume, so I don't know what your CYA should have been after you added 5# . On a 30k gal pool, 5# would add 20 ppm. BUT, it dissolves slowly. People often 'lose' it backwashing before it dissolves. This most often happens when your pump is timer operated.

Next time, dissolve it in a sock in the skimmer OR use dichlor (9 ppm CYA for ever 10 ppm FC).

I just wanted to follow up on this. My store recommends dumping all 5 lbs into the skimmer, with both the skimmer and pump baskets removed while it circulates. They also warn STRONGLY not to backwash for 3 days after adding CYA. Is this something that sounds right?

If I dissolve it in a sock (a regular sock?), does this change anything with those recommendations?

EDIT: FWIW, I have a ~26k gallon pool and adding 5 lbs on Monday brought me up to 15ppm of CYA on Wednesday.