How often should I shock?

[jake0110]

I am sure this answer exists on the boards, but I just can't find it.

My pool is running steady chlorine levels around 3. I run a frog system to maintain the level. Do I still need to shock it, and how often?

Thanks.

 

[Poolidiot]

Shock when you have a CC reading above .5

 

[The Mermaid Queen]

Welcome Jake.

 

[frustratedpoolmom]

The Frog is making the rounds....

 

[ktdave]

Depends on what your water looks like and your combined chloramine (CC) level.

Let us know what those are.

 

[Butterfly]

Hi jake0110,

Lots of answers in "Pool School". Link located at the top of each page in the sub-heading and also in my sig.

Welcome to the forum :-D

 

[jake0110]

Thanks for the welcome guys. I checked out the pool school link, and I think I have my answer. Still, let me run my situation by you. Here is my info:

I bought the pool last year, and the water quality has been great; clear, no odor. I check it frequently and I have a 150 gal saltwater fish tank, so I am used to balancing water chemistry. It is a 24' above ground pool, 14,000 gallons

I use 4-way test strips. My current readings are:

pH: 6.8 - i put in sodium bicarbonate this morning

Free chlorine: between 1 and 3 ppm

Total alkalinity: 120 ppm

Stabilizer: near 0 ppm

So..... should I shock every 10 days?

Also, should I add chlorine stabilizer, even if the chlorine remains at a good level in the pool?

Thanks again.....

J

 

[duraleigh]

Hi, Jake,

Welcome to the forum! :lol:

Uh-oh! Back to pool school :lol: :lol:

Read up on stabilizer in "ABC's of pool water chemistry". (you need some) and "BBB for beginners" and "how to balance your pool water"

Also "search" "test strips" on the forum and you'll see why few of us like them for anything.

Use Borax to raise your pH.....baking soda raises your Alk....you're a little too high already

 

[frustratedpoolmom]

Sorry for my sarcastic comment before, I'm just not a fan of the Frog.

Welcome to TFP. Before I answer your q's, I have a couple for you too!

Is this a new pool?

How are you testing your water? For example, are you using test Strips, is the pool store testing it?

It's very unlikely that if your FC is running at 3, with tri-chlor, that your CYA is zero.

I just want to clarify these two q's before we discuss shocking.

Thanks!

 

[frustratedpoolmom]

Oh I see - test strips.

Let me know about whether this is a new pool?

 

[ktdave]

Most importantly, I would suggest that you get a drop-based test kit such as the TF-100 sold by a TFP member duraleigh (http://www.tftestkits.com/) or the Taylor K-2006. The test strips are usually fairly inaccurate and hardly reliable for maintaining your pool chemistry.

As far as shocking, in my opinion, it's not something done on a "schedule" but rather when necessary. For instance, I have yet to shock my 1 year old pool, just because my regular weekly (or daily) tests have indicated that I don't need to. You will be more closely in tune withyour pool chemistry if you have a drops-based test kit that includes:

FAS/DPD test for chlorine
pH test
Total Alkalinity test
CYA (stabilizer) test
Calcium Hardness test

yes, you need stabilizer.

 

[frustratedpoolmom]

The instructions for the Frog tell you to shock 'every 2 weeks or more frequently' if hot weather and heavy bather load etc. There is a reason King tech tells you to do this.

A properly balanced and maintained pool does not require routine shocking.

Best advice I could give you is get the TF-100 test kit.

 

[Guest]

The instructions for the Frog tell you to shock 'every 2 weeks or more frequently' if hot weather and heavy bather load etc. There is a reason King tech tells you to do this.

A properly balanced and maintained pool does not require routine shocking.

It does if you want to try to maintain the pool with metals and .5 ppm FC!

 

[frustratedpoolmom]

The instructions for the Frog tell you to shock 'every 2 weeks or more frequently' if hot weather and heavy bather load etc. There is a reason King tech tells you to do this.

A properly balanced and maintained pool does not require routine shocking.

It does if you want to try to maintain the pool with metals and .5 ppm FC!

EXACTLY!!!!

 

[jake0110]

OK. So I seem to have worked things out pretty well, thanks to your help.

A couple of questions remain though:

1. What is the difference between pH and alkalinity? The guy at the pool store offered an inadequate explanation.

2. The pH increaser the store sells is Sodium Carbonate, but baking soda is Sodium BiCarbonate. What is the difference, and which one should I use?

3. What's the deal with Borax? As above, the store sells Sodium Carbonate as pH increaser, but Borax is a different chemical.

4. The store measured my Free Chlorine at 3.5, but Total Chlorine at 2.7. They do not measure Combined Chlorine. How can the TC be lower that the FC? How can I find out CC when the store cannot test for it?

5. Finally, they suggested I use CYA to lower my Total Alkalinity. Is that the right answer?

Thank you.

Jake

14,000 gal above ground pool
I'll post other specs soon.....

 

[JasonLion]

1) pH is how acidic or basic the water is. This is the one you care about. TA is a measure of how much buffering there is in the water helping the pH stay stable. When TA is very low the pH can fluctuate wildly.

2) Sodium carbonate is commonly called soda ash. It will raise pH quite a bit and TA some. Sodium Bicarbonate is commonly called baking soda. It will raise TA quite a bit and pH some.

3) Borax, as in 20 Mule Team Borax, is a completely different chemical. It will raise PH quite a bit and TA just a little.

4) The stores test results are just wrong. You should get your own high quality test kit and measure the levels yourself.

5) No! Do not try to lower TA with CYA! There are instructions on lowering TA here.

 

[frustratedpoolmom]

OMG find another pool store. They are useless, clueless and will steer you wrong.....

 

[Ohm_Boy]

How can I find out CC when the store cannot test for it?

There are three components to the chlorine content of a pool.
There is FREE CHLORINE (FC) which is the chlorine available for use as a sanitizer
There is COMBINED CHLORINE (CC) which is "used" chlorine, or chlorine which has combined with contaminants such as ammonia, sweat, etc.
There is TOTAL CHLORINE (TC), which is simply the sum total of FC and CC.

So if you know any two, you can determine the third.
TC = FC + CC
FC = TC - CC
CC = TC - FC

And I know it's been said, but you SERIOUSLY need to a) get your own test kit, and b) find another pool store. I mean, hey - I don't know the folks at your pool store, but they are certainly giving you bad advice. Real bad advice.

 

[jake0110]

I did try to buy a more comprehensive test kit, but they didn't sell any with CC, so I passed.
I will go find a new store.

Thanks

 

[revstriker]

I did try to buy a more comprehensive test kit, but they didn't sell any with CC, so I passed.
I will go find a new store.

Thanks

Even the big pool store chain near me does not have a decent (in my opinion) test kit for sale. I ordered mine (Taylor k-2006) online. Lots of members here use the TF-100 kit sold by duraleigh (a member here) and highly recommend both the kit, and the service that duraleigh provides. I know from ordering my Liquidator through him that he is very fast.