No Chlorine Reading

by Marry Ann

FC - 1.22

TC - 1.22
CC - 0
pH - 8
TA - 176
CH - 241
CYA - 0
Copper - 0
Saturation Index - 1

I've recently refilled my 5,300 gallon pool after draining it due to a high level of CYA (it was at 102).

Before emptying my pool I had been using trichlor tabs and sodium dichlor shock when needed. At my local pool store I was told to stop using sodium dichlor shock, and that I should use cal-hypo or liquid chlorine instead. I am now using trichlor tabs in a floater and liquid chlorine to shock. I was also told not to add stabilizer to my pool because I didn't need it due to its small size.

I live in Florida and my pool is in full sun all day. I'm having a hard time keeping chlorine in my pool. Should I add stabilizer after all, or could the high pH and TA affecting it?

Hi Christina. Regardless of the size of an outdoor pool, it needs CYA. Your FC will get chewed up very quickly without it. Use enough granular or liquid CYA to increase it to 30 ppm, then keep using liquid chlorine as needed to maintain a FC level of 3 - 5 ppm.

Reduce your pH and maintain it between 7.2 - 7.8 using liquid or dry acid.

The type of advice you're getting from the pool store is why so many people buy my eBooks, consults, and videos series because their pools went green or cloudy.

Thanks and have a great Summer.

All Pool Chemicals High

Inground pool--vinyl liner-- 16 x 32---opened pool--white water mold--running filter 24 hours since 4/16/2017--pool
clear but slightly cloudy in deep end.

I was unable to get a free chlorine reading all this time. My total chlorine started at 15.I have been shocking with liquid shock and finally I am able to hold the chlorine overnight.(liquid chlorine) no tabs.

I used the Taylor kit to test the water this morning 7 am and the levels are all HIGH.

FC 10
TC 10
PH 7.8-8.0
ALK 120
Calcium Harness 270
CYA 100(probably more)

I did not put any CYA in and I did NOT use tabs. The automatic chlorinator is turned off.

I tested the water before I put in liquid shock and the readings were:

FC 0
TC 1.2
PH 7.4
ALK 120
CYA 30-50

How can CYA go up if I did not add cya? everything I read says the tabs add cya but I did not turn on chlorinator and I did not use granulated anything. just liquid shock.

I have owned this pool for 14 years and always maintained it myself with barely any issues.

Hi MaryAnn

There could be some things going on here. First, the test may not have been correctly taken. Reagents might be old which can give you a false positive or negative.

CYA can only increase when CYA is added to the pool. If the first reading was 30 ppm but then 12 hours later it reads 100 ppm, that would be a concern. There's no chemical reason how the CYA can increase 70 ppm without first adding CYA.

I would suggest getting the water tested by 1 or 2 pool stores if you can, then compare it with your tests. See if there's a pattern.


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