High FC

[bjxds]

New pool owner, All summer the results have been consistent. After Debbie we received more rain than all summer and it has sunny and clear but been much cooler, Day 80's Night 60's for almost a week.

1 week ago
FC 5
CC -0
Today
FC 7
CC 0
Is it OK to swim and why did it go up and how can I bring it down?

PH,TA, and salt are all within range and same. CYA is O and always has been. I have not had a problem with low chlorine, so never added CYA. I have been running my SWG at 50% all summer to maintain 5 FC, I lowered it to 30% after testing today.

 

[Donldson]

Wow, you're burning through your SWG pretty fast by refusing to put CYA in your water. Water is probably a lot less comfy without it too...

Anyway, to answer your question, no it would not be wise to swim. The active chlorine in your water is more than 10x what TFP considers safe to swim.

 

[bjxds]

Wow, you're burning through your SWG pretty fast by refusing to put CYA in your water. Water is probably a lot less comfy without it too...

Anyway, to answer your question, no it would not be wise to swim. The active chlorine in your water is more than 10x what TFP considers safe to swim.

Now I am totally confused, how did you determine the active chlorine is 10x more?
The water has always felt good. I am not refusing to add CYA, I did not think it was needed since I have been maintaining a FC level of 3-5.

 

[Bperry]

Now I am totally confused, how did you determine the active chlorine is 10x more?
The water has always felt good. I am not refusing to add CYA, I did not think it was needed since I have been maintaining a FC level of 3-5.

Heres the link to why you need the CYA, other than you needing to replace your salt cell way earlier than necessary.

CYA Chlorine Relationship - Further Reading

www.troublefreepool.com

If your pool really has 7ppm and zero CYA, Id have to believe it would be pretty uncomfortable. Have you actually tested the CYA at zero? In any case, you really should have at least 30ppm CYA. Its way safer for your body, your pool equipment, and your salt cell.

 

[TinFoilHat]

CYA is the buffering agent and stabilizer for chlorine so it won't be an irritant to swimmers and will not burn off quickly. Keeping a high chlorine level with no buffering is uncomfortable at best. Zero will cause all the issues mentioned and more. Get with the CYA program!

 

[bjxds]

OK I am adding CYA... SLOWLY, BUT what could cause the FC to rise from 3-5 to 7?
I tested again and FC is 7. Nothing added to the pool.

 

[Bperry]

OK I am adding CYA... SLOWLY, BUT what could cause the FC to rise from 3-5 to 7?
I tested again and FC is 7. Nothing added to the pool.

Its impossible for chlorine to rise if none is added. Thats just physics/chemistry. So the suspected issue would be testing accuracy. How’d do you get 3-5
and 7?

 

[bjxds]

The same Taylor test I have been using for about 1 month.

Is it possible there is an issue with the SWG?

 

[Bperry]

The same Taylor test I have been using for about 1 month.

Is it possible there is an issue with the SWG?

If its on, itll make chlorine. If chlorine is going up then the SWG isnt off.

Assuming youre using the FAS-DPD tesy and not thr yellow OTO test.

 

[Richardya]

The CYA test is the one with the black dot. If you can see the black dot even when the tube is full, it means you are below 30 but not 0.

I am new so take what I say with a grain of salt. I originally thought my CYA was zero as well.

 

[jark87]

OK I am adding CYA... SLOWLY, BUT what could cause the FC to rise from 3-5 to 7?
I tested again and FC is 7. Nothing added to the pool.

Your SWCG is adding the chlorine. It’s hard to say what conditions may have changed that took your stable 50% run time from 5ppm to 7ppm. Maybe cloudy days where the sun wasn’t burning off the chlorine?

As others have said, rather than lowering your FC, your CYA addition will allow you to maintain FC at 7+. I maintain FC at 8-10, but I also keep CYA at 80ish - assuming I’m reading that *$*#%! dot test correctly. The higher FC gives you some added protection against algae. I learned the hard way by trying to maintain the “target” of 5.