Hm. Ok, 8 oz * 54% = 4.32 oz of CYA. 4.32 oz of CYA in a 15k/gal pool = 2.25 ppm increase. Two pucks/week = 4.5 ppm increase/wk.

For the "standard" 10k/gal pool, one puck with similar chemical composition will give you a 3.4 ppm increase/wk. You can see how people burning through 4 pucks/week can really get high CYA levels.

Michael