Didn't want to steal a thread so I am pasting a comment here to discuss it.
The OP's CYA was 80. Slam level was like 31. The comment was "It would be good to also drain off some water to dilute that CYA level down to something more reasonable in the 30-50 range before you SLAM so it's financially more reasonable in the amount of bleach you'll use."
Let me see if I can state my question intelligibly. Yes, the poster will have to pour more gallons of bleach in to get to slam level than if CYA was 30, but overall it will take the same amount of bleach to kill the algae. X amount of Algae will consume Y amount of CL as it is killed, right? The initial amount poured in may be higher but the residual amount after all the Algae is killed will also be higher.
If not, I don't understand where the CL is going