1st Test Results with TF100 Kit - What should I do now?

[fziffel]

Daily Test:
CL = 5
PH = 7.2

Weekly Test:
FC = 11.5
CC = 1.5
TC = 13
CH = 250
TA = 100
CYA = 100

This is my 1st year with a pool. It came with auto chlorinator using 3" tabs.

 

[Jezza]

You have a couple of concerns- firstly you have a high CYA which is being caused by the tabs you are using for your chlorinating. You need to consider a drain of your water to bring this level down and pull the tabs -start using bleach or liquid chlorine.

You also have a high CC which is also a concern. How does the water look?

 

[needsajet]

Welcome to TFP! Good to have you here And thanks for posting your test results.

How does the water look to you? Could you post a picture looking down at your steps, or with your brush or cleaner in the deep end? Your numbers look good except for the combined chlorine.

CYA may be higher than 100, so I'd recommend the diluted test. See #9 in Pool School - CYA

- - - Updated - - -

Haha, simultaneous help from Aus! Jezza will be awake longer than me, and he has you covered!

 

[fziffel]

The water looks very clear.

I will do the diluted CYA teat today when I get home.

So I should stop using tabs completely?

What should my CC be?

If I turn chlorinator of completely, I assume CC will drop & when desired level is achieved, I can maintain with bleach added directly to pool?

 

[Jezza]

Yes- you have to stop using the tabs now- they will continue to add CYA and that will mean more of a water drain to get it down to a reasonable level if it is astronomically high. Use bleach and the Poolmath tab to calculate your additions.

CC's should be <0.5. CC's are brought down by chlorine and sunlight although if you have organics in your pool it could take a possible SLAM to get on top of it and bring it down to an acceptable level.

But your focus now should be on establishing your actual CYA as first priority.

 

[Pool Tool]

Just to elaborate, CC's are not something that is directly added to your pool. Think of CC's as spent FC. They are a byproduct, a leftover, of FC oxidizing organic material. A healthy, well balanced pool will have less than 0.5 ppm CC's. As Jezza noted, sunlight will remove CC's, this is why leaving a cover on can cause a high CC reading temporarily, as well as raising FC levels will eliminate organics in the water and reduce CC production.

Word of caution tho, do not try to use CC's as a measure of your FC effectiveness, i.e. "my pool is cloudy and I raised FC, but I am not generating any CC's so it must not be algae." Measurable CC may or may not be formed when FC kills something or it may simply be burning off by sunlight (UV) prior to sampling.

FC = Good, CC = Bad. Like your case with CC of 1.5, it is telling you that there is something in your water that your FC is fighting necessitating a SLAM - even when your water is otherwise clear!

 

[fziffel]

Wow, very helpful - thank you.

So are my FC's O.K.? Too Hi?

I am going to stop using my chlorinator. Should I start to add bleach immediately ow wait until FC's measurement requires additional chlorine?

What is the sweet spot for FC's?

 

[Pool Tool]

Here is the FC sweet spot based on your CYA level. Pool School - Chlorine / CYA Chart

Wait until you can do the diluted CYA test. It may come back higher, which would definitely necessitate water replacement.

Provided your CYA stays at 100 ppm, your FC of 11.5 is pretty good. I would prepare to be able to add bleach/chlorine (same thing) within a day. Do not let FC get below 7 or 8 ppm.