What to do about CYA?

[Dewdrops3]

Can I have some guidance about CYA and FC levels please? I added enough stabilized chlorine last Wednesday and Thursday to bring the levels up to 50ppm CYA. Testing it today I still can't get it to register on the k2006 test.

With the addition of the stabilized chlorine last week the pH level went as high as 16. With a mix of rain and sunshine this week the FC is down to 3.

Here are the full test results:

Temp 84F
pH 7.6
FC 3
CC .5
CYA 0
CH 225
TA 110

I've read many posts stating to assume that the CYA is in the pool and add Chlorine appropriately to maintain the levels on the chlorine/cya chart. Is this the case for the results of my pool water, too?

If I add chemicals according to the pool calculator the pH will be lowered by the calcium chloride that raises the calcium hardness. The addition of stabilized chlorine should raise the CYA and FC. The CSI is currently 0.17

Should make the additions and then kinda forget about the CYA number on the test?

Thanks for your help.

 

[frustratedpoolmom]

Any increase in PH from chlorine is temporary and the PH drops back to normal when the FC level does. What was the "stabilized chlorine" that you added, and can you elaborate on how much "enough" was (specific amount)?

Don't worry about your CH right now.

How does your water look?

 

[Dewdrops3]

The water looks great. Clear and sparkling.

In total over two days I added 26oz of sodium dichloro-s-Triazinetrione from Aquarius.

 

[frustratedpoolmom]

That makes no sense does it? lol

How are you testing the CYA?

 

[Dewdrops3]

Outside, indirect light at waist level using my new k2006

 

[frustratedpoolmom]

back to the sun? cold water or warm water? Did you mix, let it sit for a minute, then mix again?

 

[Dewdrops3]

I did an OCLT on May 18 with zero loss.

Mixed for one minute didn't let it sit...oops. Yes, back to sun.

 

[Dewdrops3]

Warm water 84F

 

[dmanb2b]

I doubt it may be bad r-0013, but in case you need to confirm TFtestkits.net sells a 50ppm CYA test solution, so you can use that to guage/calibrate current test results.

 

[Dewdrops3]

Hopefully, Apollo Piscine sells it, too. Any other way to test the reactant? They should put the date of production on the bottles. I only received mine a week ago.

 

[frustratedpoolmom]

It should be there but you are testing correctly which makes me wonder what was in there. Was it a bottle or bag? Dichlor doesn't usually go bad.

 

[Dewdrops3]

This is what I'm using.

 

[JasonLion]

That is dichlor, which raises FC, CYA, and lower PH. If you add enough to raise FC by 10 it raises CYA by 9.

 

[Dewdrops3]

Thanks. Should I add in increments until my CYA registers? Perhaps there is only about 15ppm in the pool if my FC was up to 16 at its highest...it was in around 1.5-5 on other days since the new fill last week. I haven't added any bleach yet since the dichlor is keeping the FC up high enough.

 

[frustratedpoolmom]

I'm wondering if someone replaced the dichlor with something else and returned it? Yes you can add in increments or find CYA separately.

 

[Dewdrops3]

Thank you. I've added 8oz. I'm thinking that I should have at least 60ppm in the pool already. This addition should add another 24. If this works, the numbers will be high, if so, I'll drain some water and refill to bring the CYA back to between 30 and 50.

Should I wait to test for another week?