Day 7 of SLAM, CC Won't Go Down

flpool007

New member
Apr 9, 2022
2
Florida
Was having some algae issues. Began the SLAM process, monitoring every 2-3 hours for the first few days. I had to leave for an overnight trip so took it to the mustard algae level in the morning before I departed and tested when I got home the next evening. The FC was slightly below the SLAM level (1.5 under). NE FL with sunny and very hot weather so between that and whatever the chlorine is working on, significant drop over 2 days.
Most recent numbers are:

FC - 15.0
CC - 2.0
pH - 7.8
TA - 90
CH - 450
CYA - 40
CSI - 0.37

When I started the CYA was 50 but went down to 40. I have brushed and vacuumed the pool multiple times, including the light niche and skimmer. No ladder, just some steps in the pool to clean. Have run the water through the waterfall return for several hours. New reagents from the spring refill sale and cleaned the chlorine testing container with bleach to be sure there was nothing left behind. Water looks clear, OCLT has been .5 and 1 the past two nights but the CC has ranged from 1 to 2.5 the whole time. Added acid at the beginning to bring the pH down and am using liquid chlorine from the pool store but nothing else has been added and no one has been swimming in the pool.
Am I missing something or do I just need to keep waiting?
 
Last edited:
If you started with a CYA of 50, continue to use that CYA number rather than the 40 you tested later.
For CYA 50, FC is 20.
During the SLAM, only test FC and CC.

pH test is invalid when FC > 10.
Did you reduce pH to 7.2 before starting the SLAM?

Clean your test vials with rubbing alcohol, dry thoroughly and run the CC again.
 
If you started with a CYA of 50, continue to use that CYA number rather than the 40 you tested later.
For CYA 50, FC is 20.
During the SLAM, only test FC and CC.

pH test is invalid when FC > 10.
Did you reduce pH to 7.2 before starting the SLAM?

Clean your test vials with rubbing alcohol, dry thoroughly and run the CC again.
Got it.
I will use the CYA of 50 and focus on the FC and CC the rest of the SLAM.
I did add acid prior to the SLAM to bring the pH down to 7.2.
After cleaning and drying with rubbing alcohol my FC is 17.5 and CC is 1. I've added chlorine to bring the FC up to 20 and will monitor and add as needed the test of the day today.
 
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