The formula is about 3.3 ppm CYA for 8 ounces in 10,000 gallons. So,

3.3 * (7/8) * (10000 / 27038) = 1.07 ppm CYA per 7-ounce puck in 27,038 gallons. The accurate calculation gives 1.08 ppm CYA (the 3.3 was rounded).

I'm not sure what you were looking for.

Richard