I've been following the instructions for SLAM-ing my pool since Friday 6/12. The pool has gone from swamp green color to an Aqua Blue. When I started the CYA was very high, close to 80 with Zero FC, I retested the CYA after adding much chlorine the last few days, and my CYA is now down below 30. My question, is the CYA test valid during SLAM-ing, or is it skewed like the PH test? If it is valid, should I also concentrate on getting my CYA back up to 40?