First Test Numbers

[hende]

After a long weekend of heavy pool use I did my first official test last night. I received my test kit on 7/2 and tested, but that was only 3 days after adding stabilizer and I wanted to wait a full week.

7/2
FC 5
CC 1
TC 6
TA 140
CYA 43
PH 7.2

7/6
FC 8
CC 0
TC 8
TA 150
CYA 58
PH 7.5

In previous years I would automatically shock after a long weekend with high temperatures, but I held off last night. If I understand the test correctly, my numbers are pretty much on target with the exception of a high FC which should lower on its own. Am I reading this right?

 

[kimkats]

Great job!

Looks like you are close to being spot on.

Your TA looks a little high. You might want to lower it to around 100 or so.

Look how great the TFP way works and saves you money! Testing is power!

Kim

 

[Butterfly]

Nice work

Your FC last night was about perfect, NOT high

With a CYA of about 60, keep FC between 5 and 9, and never below 5.

So, each evening dose the pool up to 8 or 9 FC. The next evening, make sure it has stayed at 5 or more. You may need to play with this a little until you learn what your pool's FC appetite is.

About that TA, each time the pH reaches 7.8, lower it back to 7.2 with muriatic acid. By the by, the TA will lower.

No need to do anything special unless you are having to lower pH so often that it is annoying.

 

[hende]

Thank you for your input.

Just so I understand the BBB method correctly - say when I test tonight the CH comes up at 4. If my target CH is 8 I would add a little under 2 gallons of 8% bleach, directly in front of the return?

 

[Richard320]

Thank you for your input.

Just so I understand the BBB method correctly - say when I test tonight the CH comes up at 4. If my target CH is 8 I would add a little under 2 gallons of 8% bleach, directly in front of the return?

That's it. I come up with 1.7 jugs.

It's really just that simple. When pH climbs to 7.8, add acid to get it back down to 7.2. Just space the chemical additions apart at least half an hour.

 

[Kiss4aFrog]

Welcome to the forum Hende

No need to shock with your numbers. If you maintain the proper FC level for your CYA level your pool will stay sanitary, clear and sparkly. If you know you're going to have extra bathers you can always bring that FC level to the high end as you know a lot of it will be used but shocking afterwards isn't necessary and is just extra work and $$ you don't need to spend.

From this table in "Pool School", http://www.troublefreepool.com/content/128-chlorine-cya-chart-slam-shock (tab at top of page) you can see for a certain level of CYA you need a minimum of "X" chlorine and then it gives you a target level. You want to be around the target but not drop below the minimum. Below the minimum is where algae starts and also there isn't enough chlorine to kill the "stuff" you want killed that's floating around in the pool. This is where pool stores get it wrong as they will usually say if you have 1-3ppm FC you are good. Well you are if you have low CYA but if it's higher like yours (and mine) 1-3ppm isn't going to keep you algae free and your water may look crystal clear and clean but there can easily be things in there alive that shouldn't be.