Hello, we have been having a difficult time keeping algae blooms from returning week after week following leslies pools recommendations. That led me to finding this forum. I really like how simple everything has been explained. I am just having a hard time coming to terms with the recommended chlorine levels being much higher than what leslies and my pool builder tell me. They say to keep between 2 and 4 and not swim when over 5. This method says to keep 5-9 based on my cya. I am trying to get some comfort around having those higher levels. Can someone explain it to me?
Newbie, why keep chlorine higher than traditional measures recommend
- Thread starter Sarahgeff
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- May 3, 2014
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Welcome to the forum!
First, let's try a short video on the FC/CYA relationship -
The pool stores/industry are still stuck in the 1970's, though some are changing. A very detailed discussion is in Pool Water Chemistry
I suggest you read ABC's of Pool Water Chemistry.
First, let's try a short video on the FC/CYA relationship -
The pool stores/industry are still stuck in the 1970's, though some are changing. A very detailed discussion is in Pool Water Chemistry
I suggest you read ABC's of Pool Water Chemistry.
- May 3, 2014
- 58,690
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Another article a bit less technical -- CYA Chlorine Relationship - Further Reading
Remember, drinking water is approved by EPA to have up to 4 ppm TC in it. The ranges you stated in your post are based on 0 CYA, essentially drinking water. TFPC uses the effect of CYA on the chlorine in the water. Or active chlorine. TFPC managed water chemistry with a CYA of 50 ppm and 10 ppm FC has a fraction of the active chlorine in it that drinking water has.
Remember, drinking water is approved by EPA to have up to 4 ppm TC in it. The ranges you stated in your post are based on 0 CYA, essentially drinking water. TFPC uses the effect of CYA on the chlorine in the water. Or active chlorine. TFPC managed water chemistry with a CYA of 50 ppm and 10 ppm FC has a fraction of the active chlorine in it that drinking water has.
reggiehammond
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- Oct 4, 2020
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Good for you - you’ve already figured out the trickiest part - the FC/CYA relationship.
Ask yourself how 2-4ppm can work with 0 CYA, 50 CYA, and 200 CYA? It can’t and that’s where the pool store thinking breaks down and you end up with algae and costly store visits that only keep you on the path to more $$ at the pool store.
Get a good test kit, either the TF100 or the Taylor K2006C, find out the true state of your pool and you’ll find that it’s much easier than you’ve experienced thus far!
CYA’s essential roll in all of this is to keep the FC buffered. So you will have higher levels of FC, but less active FC due to the buffering effect. FC is nothing to be scared of - a TFP method pool does not smell of chlorine, does not irritate skin, eyes etc. It’s actually the opposite!
Ask yourself how 2-4ppm can work with 0 CYA, 50 CYA, and 200 CYA? It can’t and that’s where the pool store thinking breaks down and you end up with algae and costly store visits that only keep you on the path to more $$ at the pool store.
Get a good test kit, either the TF100 or the Taylor K2006C, find out the true state of your pool and you’ll find that it’s much easier than you’ve experienced thus far!
CYA’s essential roll in all of this is to keep the FC buffered. So you will have higher levels of FC, but less active FC due to the buffering effect. FC is nothing to be scared of - a TFP method pool does not smell of chlorine, does not irritate skin, eyes etc. It’s actually the opposite!
Last edited:
- Apr 10, 2018
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I had the same concerns you did when I first learned about TFP. I had a two-year-old daughter at the time and was worried about the effects of the higher FC levels. It's been over three years now and we've seen no negative effects. No green hair, no faded bathing suits, and no red skin or eyes. TFP methods are based on science, not sales. Steer clear of the magic potions and fancy testing devices found in the pool stores. Invest in a quality test kit instead.
Best of luck!
Best of luck!
Last edited:
- Jul 17, 2019
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I'm not as sciency as the others on here, but here are the 3 main things that I see where TFP is different:
1. We test our own water with a quality test kit and do not trust pool store testing and advice
2. The FC/CYA ratio is the cornerstone of TFP. As you noted, traditional methods have a set FC range, and do not take CYA into account.
3. We understand that all forms of solid chlorine add chlorine plus either calcium or CYA. Both calcium and CYA can build up over time and cause problems. That is why we recommend liquid chlorine or salt water for your daily chlorine needs.
Welcome and hope that helps.
1. We test our own water with a quality test kit and do not trust pool store testing and advice
2. The FC/CYA ratio is the cornerstone of TFP. As you noted, traditional methods have a set FC range, and do not take CYA into account.
3. We understand that all forms of solid chlorine add chlorine plus either calcium or CYA. Both calcium and CYA can build up over time and cause problems. That is why we recommend liquid chlorine or salt water for your daily chlorine needs.
Welcome and hope that helps.
…Plus the proof is in the “proverbial Pudding”. I maintain my CYA at 70/80 all year and keep my FC at a minimum of 7. I’ve had my pool 4 years and have NEVER had a speck of algae in my pool. Nor have I ever “shocked” my pool. Crystal clear, clean water for 4 straight years. Not really much more to say. TFP Method works.
this is my first full season with my pool - i thought my water looked good the first month i opened the pool - I was running a FC of about 4 and a CYA of 30 - last week I brought my CYA up to 70 and my FC up to 7.5 - my father saw the pool yesterday and commented on the clarity of the water. I went from what I thought was a clear pool to a really clear pool in just a week without shocking by simply just bringing my levels of the TFP recommended levels. I am confident that if I just maintain these levels through testing and tweaking I will have sustained great results. In doubling my FC and CYA there have been zero noticeable effects on how the water smells or feels. My kids have not complained or mentioned any difference - there are zero red or stinging eyes.
LoneWolfArcher
Bronze Supporter
This is a great point. And I would want it higher than that if people were swimming in my drinking water!
Excellect responses. This gives me a lot of comfort
Basically with CYA in your water only a small percentage of the chlorine is active and the rest is bonded to the CYA until it's needed. This is why people who follow pool stores get algae at some point because they have too much CYA and not enough chlorine.
I wonder if there is an experiment that could help put people at ease in regards to the cya/chlorine chart. Like a bucket of tap water with 4ppm of chlorine and another bucket of water with 50cya and 8ppm of chlorine. Leave various articles of clothing in each bucket and see which one fades clothes first. Could help overcome some fears.
Ooohh... I feel an idea for one of my kids' future science projects forming!
LoneWolfArcher
Bronze Supporter
We all have to start somewhere. We were all skeptical at one point. It's hard to shake being pool stored.
- May 11, 2021
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On The Deep End there are some very interesting posts where ChemGeek demonstrates in detail the relationship between FC and CYA and how it compares to a pool without CYA (the base line for the 1-4ppm of FC). All formulas and calculations included.
I’ve always understood the difference in that the FC is bound to the CYA and not active, but the drop test still detects it in the water.
- May 11, 2021
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That is because Cl has a weak binding with CYA. So it retain its oxidizing power, but not its sanitizing power.
In a very high level explanation… When you have FC above the minimum for your CYA level part of the Cl will be HOCl (hypochlorous acid) that is the actual sanitizer and the rest will bound to CYA. The thing is the CYA on the top of your water will protect to some extent the HOCl below it.
One of the advantages of having FC at or above the target for your CYA level is the HOCl will sanitize the perspiration on your skin and you still have enough oxidizer (Cl bound to CYA) to immediately oxidize the resulting CC leaving your skin with almost no “chlorine” smell.
In a very high level explanation… When you have FC above the minimum for your CYA level part of the Cl will be HOCl (hypochlorous acid) that is the actual sanitizer and the rest will bound to CYA. The thing is the CYA on the top of your water will protect to some extent the HOCl below it.
One of the advantages of having FC at or above the target for your CYA level is the HOCl will sanitize the perspiration on your skin and you still have enough oxidizer (Cl bound to CYA) to immediately oxidize the resulting CC leaving your skin with almost no “chlorine” smell.
There are a lot of great comments on this thread that discusses the cornerstone of TFP
I always think about as
It would be beneficial if the key points could be summarized and put in 1 document and have it on the main page.
READ THIS TO UNDERSTAND THE TFP METHODOLOGY - or something similar.
Regardless, the TFP methodology works, as proven by thousands of users.
I always think about as
- Have a good test kit and do your own testing
- Understand the CYA/FC chart
- Read the ABC's of Pool Chemistry
It would be beneficial if the key points could be summarized and put in 1 document and have it on the main page.
READ THIS TO UNDERSTAND THE TFP METHODOLOGY - or something similar.
Regardless, the TFP methodology works, as proven by thousands of users.
- May 3, 2014
- 58,690
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
