Chlorine Levels

May 9, 2007
League City TX
Newbie question. When should I be measuring my chlorine levels, after the pump has run all day or in the morning before the pump comes on? Normally I run the pump from 7am-3pm. Most recent numbers are:

FC: 7
CC: 0
pH: 7.6
TA: 100
CH: 350
CYA: 70

I know the chlorine is a bit high but I started adding Borax. After I added 6 boxes I noticed that the chlorine level has been creeping up even though I have been dropping the output of the Jandy Aquapure.


Well-known member
Jun 22, 2007
Atlanta, GA
FC 7 isn't really high at 70CYA. I have 80CYA and keep my pool between 6 and 8. It keeps it crystal clear.

I measure mine after the pump has been running at least 30 min. If you measure in the morning, you might pick up a pocket where the chlorine has been busy and is used up. I generally sample about 8 inches down in front of the skimmer. Sampling near a return will have a higher FC and PH level because of the SWG.