Can someone check my math and see if I'm doing this correctly?

I have a pentair IC 40 which claims to produce 635g of 'pure chlorine' per 24 h period (I assume this is at 100%).

so I run my pump 12 hours (3 hours, 4 times per day due to time of use pricing). I feel that gives sufficient turnover and skimming action..

I've read I need to replace about 2.5 ppm daily of chlorine.

SO... I *think* this is correct:

according to pool math, 635g of Chlorine Gas (I think) is a rise of 6.4

in 12 hours that's a rise of 3.2

running the unit at 80% should give me 5.12ppm in 24 hours, so at 12 hours run time it should be just over 2.5

Am I making sense?

Joey