Newbie with a 21' AG pool, wondering about copper

[Watermom]

CC of 0 is good. That is what you want!

[The Frant]

I tested my water today and my FC was 4, CC was 0 and CA was 40. I picked up a box of the 1lb dichlor bags from Sam's. I have been using that for the last couple of days.
How fast does CA usually drop? Should I continue to use the dichlor or do CA levels stay good for a while?

[BigDave]

CYA is lost from backwash, splashout, and sometimes bacteria will consume it if chlorine is depleted. Once you get it where you want it, it should pretty much stay.