No. What's important is the FC is in the target range. It doesn't matter if you had to add .5 ppm or 5ppm. The FAS-DPD test allows us to add only what we need with little waste. That's one of the reasons many of us say it is an investment that pays for itself in bleach savings. By keeping your FC in or just above target for your CYA, you're keeping your FC well protected from sun degradation while maintaining a responsible buffer of available/active sanitizer to oxidize/kill contaminants that would love nothing more than to green your pool and get you sick.do you still put in the "typical" 2-3 ppm?
3 - 4 ppm loss of FC during the day is to be expected.Darn...I just tested again (3PM EST, six hours after my morning test)
The FC has dropped to 11.5 ppm! Why?
And now the CC is a full 1.00 ! This morning it was essentially "0.00"!
Any ideas as to what may be happening? Today there is not much direct & strong rays from the sun either.
Expect to see some CC from time to time, but then later on expect it to be gone. The idea with monitoring them is to use it as an indicator if there is a problem, both by single reading high values like 1.5+ or continuously having 1.0+ all the time. At least that's my current understanding...I'm always learningCombined chlorine is an intermediate breakdown product created in the process of sanitizing the pool. CC causes the "chlorine" smell many people associate with chlorine pools. If CC is above 0.5ppm, you should SLAM your pool. CC indicates that there is something in the water that the FC is in the process of breaking down. In an outdoor pool, CC will normally stay at or near zero as long as you maintain an appropriate FC level and the pool gets some direct sunlight.