Shock vs SLAM - Difference? And WEEKLY?!?

Jan 13, 2015
35
Arkansas
I have ready the thread on SLAMing so I have a very *basic* idea of what it is. I have been searching the internet on basic saltwater pool chemistry and site after site said that ALL pools, including those with SWG, have to be shocked "regularly" - about once a week in the warm, summer months when pool use is high. That sounds like A LOT of shocking.

And some sites are saying that SWG are actually more expensive and harder to maintain than a regular chlorine pool that "you just put tabs in."

Are these just examples of bad pool care tips bc it has me a bit apprehensive at the thought of 1) shocking the pool that often and 2) that I made a mistake with the SWG and sand filter.

<sigh>
 
I have had my pool for almost two years now. I have never "Shocked" my pool. My water is a clear as can be as you can see in my avatar. I did SLAM my pool once. My pool builder had installed the liner and filled the pool, but didn't turn it over to me until several weeks later after he had finished the concrete, bonding, etc and by that time it had a green tint. So I SLAMMED it that once and my water has been crystal clear ever since. In fact, I often get compliments and questions from people the first time they get in my pool regarding the "feel" and "cleanliness" of my pool water.
 
We use the term SLAM to differentiate what we teach from what everyone else calls "shocking"

If you maintain adequate FC levels for your CYA (see the FC/CYA Chart), then problems are VERY unlikely to develop so there is no reason to weekly add a bunch of chlorine. We only SLAM when there is a problem.

Usually it is the uninformed that recommend the weekly "shocking" which they try to use as a band-aid ... because they do not understand the FC/CYA relationship.

I would suggest you stop searching the internet as you have found the best place for unbiased information here at TFP.
 
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Those are just bad examples. :) The TFP method does not simply "shock" or "super-chlorinate" a pool as typically advised by the local pool store. We do what's called "SLAM". SLAM is significantly different than an overnight “spike” in chlorine, and can take a few days (perhaps even a week or two) to properly complete. The proper test kit is extremely important to properly conduct a SLAM. So SLAM is the term TFPC uses when we “Shock” our pool to a higher “Level” of Free Chlorine (FC) and “Maintain” it that way until 3 objectives are met. Anyone who says a pool should be shocked, super-chlorinaed or anything else on a regular basis simply isn't maintaining their free chlorine level properly. If they were, then no such suggestions would exist. We (TFP) only SLAMs when it is required.

The comment about SWGs being more expensive than just putting tabs in is wrong as well for many reasons. Those who are familiar with TFPC know we don't use "tabs" on a regular basis anyways.

That's just some bad info above. The links below in my sig will be your best ally if you have questions. Have a great day.
 
The people who say you "need" to shock are the same ones who think it is so easy to just dump in tabs and everything works great... until it doesn't...

The TFPC methods work great, but they can not be mixed with other 'methods'. I put methods in quotes because "pucks and prayer" is not a real method. If you want to be in control of your own pool then this is the place to be. Let those other people giving their 'advice' dump in pucks and hope for the best.
 
Here at TFP we MAINTAIN our pools so they do not get to where they need to be "shocked".

If a pool owner does not have their own test kit they have to rely on pool stores to test for them. Pool stores NEED to sell stuff to stay in business so............not good.

I had to do a mini SLAM one time when my husband did not do his only job with the pool-----brushing the sides at least every other day. "I don't see anything." So I jumped in and ran the brush ONE swipe on the wall and a cloud of yellow came off! He just hung his head and jumped in to take the brush from me and finished brushing. He now brushed most days without being asked LOL.

Kim
 
I have looked at the tests, gone through Pool School (several times), watched the test videos, and I think I get how to do the tests and what levels I should be looking for. I definitely plan to order one and practice before the pool is open.

What I don't get is how often you do each test? What do you attend to first, second, next....if numbers aren't right (order of importance)? And what do you add to correct the different balances when they are wrong?

This kind of stuff makes me feel so ignorant. I like things that are cut and dry - always do this first, this second, this third - steps that never change and are almost mathematical. If I understand everything I have read in Pool School and on the forums, that doesn't exist. There is no "set" order to test for/correct every single time for every single pool. Correct?
 
Correct, what needs to be adjusted often affects the best order to do it in.

Usually you only need to test FC and pH every 1-2 days.
Some others maybe test weekly and others monthly.
 
If your pool has all recommended levels in line then it's only a matter of testing for pH and total chlorine daily. Add bleach or dial in your SWG according to the TC (total chlorine) level. If pH is high, above 7.8, add acid to bring it down. That's it.

If you're just filling a pool, it's important to test for everything. FC, CC, pH, CYA, TA and CH. The most important things you MUST know to care for a pool are CYA level, FC and pH. The CYA level determines how much FC you must maintain to prevent algae. The pH determines the comfort of your swimmers and the longevity of your pool surfaces and equipment.

I test my pH and TC every day. Adjust as needed. Bleach is every day, acid is very seldom now that my TA is happy. Once per week I test FC/CC, pH, TA and sometimes CH. CYA should only be tested after you have significant water replacement outside of normal evaporation.
 

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Pool School - ABCs of Pool Water Chemistry

Do your tests in the order above. They are in order of importance. Notice that the PH and TA are close together. They "work" together.

How often to test:

FC-EVERY day. I test and add in the evening. The reason is so the FC can work all night without worrying about the sun taking any of it. Some people like to test and does in the morning. YOU will find what works best for you and your life.

PH-At first test every day. You will learn your pool and what it does and needs. Once you start seeing a pattern you can back off to every other to every three days.

TA-Test every day until you see what your pool does. For my pool once I get the TA set in the early Spring I do not have to really mess with in again.

CH-I don't worry with it because I have a vinyl pool.

CYA-Once you add it you should be done. After BIG rains and drains you should test it again just to make sure.

I hope this helps.

Kim
 
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I have looked at the tests, gone through Pool School (several times), watched the test videos, and I think I get how to do the tests and what levels I should be looking for. I definitely plan to order one and practice before the pool is open.

What I don't get is how often you do each test? What do you attend to first, second, next....if numbers aren't right (order of importance)? And what do you add to correct the different balances when they are wrong?

This kind of stuff makes me feel so ignorant. I like things that are cut and dry - always do this first, this second, this third - steps that never change and are almost mathematical. If I understand everything I have read in Pool School and on the forums, that doesn't exist. There is no "set" order to test for/correct every single time for every single pool. Correct?

most people just follow the test directions in the tftest kit and go top to bottom... I cant remember exactly the order..

there is no wrong order.. :)
 
In five years I've never had to "shock" or SLAM my pool. I just keep enough chlorine in there and algae never grows. I get 12.5% bleach in returnable jugs from the mom-n-pop pool store. Costs me about a buck a day in season, less when it's too cold to swim, but the pool is never "closed."

Here's a graphic I seldom use that shows a "shock" and a "SLAM." Except the SLAM needs some work so it stays blue forever and ever.
attachment.php
attachment.php
 
This is SUPER helpful but why do you "not worry with it" (CH) because you have vinyl? I only ask bc mine will also be vinyl. And yes, we are just a day or two away from filling.

Pools with a finish other than vinyl have to have CH levels maintained to keep the water from pulling calcium out of the finish. There's no calcium in a vinyl liner, so you don't have to worry about it.


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