Do you already have the AquaShock Plus? It's 58% dichlor but that means the actual chlorine percent is much lower, since 100% dichlor is only about 55% chlorine. Your product is 58% x 55% (0.58 x 0.55) or 32% chlorine!

Do this:
1. In the evening, brush and then add 4 gallons of household bleach for each 10,000 gallons of pool water (24 ppm dose)
2. Test your CYA level, and report that here.
3. Tell us what your pool dimensions are, or what your gallons are.