Excessive FC loss? Or something sinister.

tadcpht

Well-known member
Jul 17, 2012
95
Forest, VA
This morning (715am)
FC 15.5
CC 0.5
Cya 40
pH 7.5
Alk 110
This afternoon (4pm)
FC 8
CC 0.5
Cya pH alk same.
My pool gets sun almost the whole day.
Is this normal FC loss for a day with my cya or could something nasty be in the water? I am planning on an OCLT soon (prob Tuesday). I'm am almost out of R-0871 solution which is why I haven't started the process yet. Thanks for any replies.
 

AimeeH

LifeTime Supporter
TFP Guide
Apr 2, 2012
2,028
Columbia SC
Wellllllll, do you suspect something sinister since you had your chlorine at 15.5 with a CYA of 40? That is shock level not maintenance level. So with that.....I'd suspect something sinister.
 

tadcpht

Well-known member
Jul 17, 2012
95
Forest, VA
The last few days we have had heavy bather loads and seemed like my FC would drop more than it should. So I brought up to shock level and wanted to see how much I lose in a typical day. Just seems like a lot