Slam for Algae maybe Mustard with High Cya

[Haleakala]

With a Cya of about 60-70 would it be more efficient for the SLAM (less bleach) process to drain/refill to lower the Cya somewhat? Can the higher FC levels held for SLAM/Mustard elimination harm the vinyl liner? Getting heavy rains so I drained a few inches last night. I have an auto chlorinator and wasn't paying proper attention to the Cya level which crept up, so my FC levels were maintained too low. Looking to get rid of organics prior to closing. Water is very clear, I just thoroughly cleaned and regenerated the DE filter as pressure crept up too much (new pool, lots of dirt during install). Using Taylor K-2006 kit. I have read the SLAM process and I guess I follow normal SLAM shock levels first, then bring it up to Mustard shock and maintain that for 24 hours, with daily brushing? Should the light be removed from the niche? I bought 11 121Oz bottles of 8.25% bleach (yields 7.86% active chlorine). I think pool match shows I'll need some more. What is up with my low CH? I did fill with well water. Measured it twice and it really is that low. Where can I buy calcium chloride?
FC 3.5 CC<1.0 Cya 60-70 TA 80 CH 60 (very low) 31K gal

First post!

 

[tim5055]

Ignore the CH, you don't need to add that to a vinyl pool

Yes, lowering the CYA will reduce the amount of chlorine needed for the SLAM. Yes, there may be algae hiding in the light or any other place with poor circulation so it is better to clean it if possible during the SLAM.

Next year you will need to stay on top of the CYA, maybe stop using the pucks.