CC has me completely confused

CactusGirl

Active member
May 5, 2019
43
Phoenix
I successfully SLAMed my pool, beginning last Sunday, ending Sunday, 5/12. The last time I added liquid chlorine was Saturday night. Prior to adding 1.75 gallons 10% liquid chlorine, my test results were: FC 11.5, CC 0, TA 100, CYA 54-ish. My SLAM goal is FC 21-25.
Sunday the water was clear. I didn't test at all and went to work. Today I tested and the results are as follows:
Temp 80° (highest it's been this year)
FC 10
CC 0.5 (what?!?!)
TA 100
pH 8.2 (maybe?)

I haven't added any liquid chlorine yet. The pool is totally clear. Where is the cc coming from? The entire time I slammed I had no CC! And all of a sudden now I do?! What happened?

Please explain to me, like I'm five what CC is. I already read ABC's of Pool Chemistry and the other articles several times.
What should I do?
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
10,784
Northern NJ
CC of 0.5 is not indicative of any problem. Normal daily CL sanitation creates some CC. You had something fall into your water that the chlorine took care of. That level CC comes and goes and is normal.

Btw, your CYA is 60 and your SLAM Process FC should be 24 or higher. We always round up. If the dot disappears between 60 and 50 you call it 60. You can’t eyeball values between the lines since the CYA scale is logarithmic, not linear.

Also, when doing a SLAM Process just test FC until the FC is below 10. The pH test is unreliable when FC is above 10.
 
Last edited by a moderator:

CactusGirl

Active member
May 5, 2019
43
Phoenix
CC of 0.5 is not indicative of any problem. Normal daily CL sanitation creates some CC. You had something fall into your water that the chlorine took care of. That level CC comes and goes and is normal.

Btw, your CYA is 60 and your SLAM Process FC should be 24 or higher. We always round up. If the dot disappears between 60 and 50 you call it 60. You can’t eyeball values between the lines since the CYA scale is logarithmic, not linear.

Also, when doing a SLAM Process just test FC until the FC is below 10. The pH test is unreliable when FC is above 10.
I SLAMed at 21ppm and it cleared everything. I'm happy with that!