The pucks have given you a lot of CYA. 90 is very high. Your shock level is 20-22ppm FC. http://www.poolsolutions.com/gd/best...e-chart.html#a

Use bleach or liquid chlorine rather than bagged shock as that will not raise your CYA level.

Have you considered doing a partial drain and refill of the pool to lower your CYA?