I've searched the forum for this info. But can't seem to locate. I'm replacing my pool liner and wondering if there's a concensus of what level (ppm) of chlorine to keep in the pool so as not to degrade the liner? I have managed to bleach my liner out completely by maintaining levels in the 5-7ppm range over the past several years after switching to the TFP method. Of course this also included various and sometimes lengthy shock sessions when I was first getting started I'm hoping to avoid turning my liner completely white this go round. Is there a certain level not to exceed? I understand the relationship between FC and CYA. I would prefer to allow my FC level to dictate my CYA level rather than the other way around. Sadly my liner is still in good condition. I'm only replacing for aesthetic reasons. I also have a hunch that my FC levels may have possibly led to pipe/valve degradation as well as I am also having a series of leaks repaired.
Chlorine level and vinyl liner degradation
- Thread starter aralph
- Start date
Since the FC level constantly changes, that won't work.
Can you post a set of current test results?
How do you get the chlorine into your pool?
Is it easy to show a pic of the bleached liner?
All the guidelines TFP suggests are safe for liner pools so certainly we should find out what's wrong BEFORE you replace your liner or the same thing will happen again.
Someone on here did a test indoors. One with like 20ppm chlorine levels and minimal CYA and the other with no chlorine. Both looked the same after a month. Not 100% sure if my numbers are right, but someone did a test here of some kind.
Likely the sun / environment bleached yours especially if the liner above the water line is bleached as well.
At least that is my guess.
Likely the sun / environment bleached yours especially if the liner above the water line is bleached as well.
At least that is my guess.
Ralph:
Take a look at the thread below. Each year, I take pictures with the new liner, pool floor and upload. I am on the 5th season, and one thing that is noticeable is the corners, were the pool walls meet the sand/mix base in the mid and deep end (about 1"). The area seems to be more faded (almost bleaching out), but not there yet. Please note that this has nothing to do with any powdered chemicals either, just the sun only.
Maybe once or twice per year, I will bring to SLAM level and allow levels to drift down just as a cleaning session. My FC levels have always stayed within the parameters of the CYA/FC relationship prior to the SWG. On average, over 5 months each year, I would say my levels have been maintained at around 5.5 ppm and nothing lower with 60 CYA. This is the average of the 20 weeks that the pool was opened. The extended testing is done weekly.
Liner fading progression after 3 years
I feel Dave has hit this on the nose. If you can provide us data, that would be great. A few items that you failed to mention is how long have you had the pool, how old is the liner, and are you the only owner? If you purchased the home from someone else, there is not enough information. Fading becomes more noticeable each year after the first few years. One would assume that after 7-10 years, the progression is a lot faster.
Take a look at the thread below. Each year, I take pictures with the new liner, pool floor and upload. I am on the 5th season, and one thing that is noticeable is the corners, were the pool walls meet the sand/mix base in the mid and deep end (about 1"). The area seems to be more faded (almost bleaching out), but not there yet. Please note that this has nothing to do with any powdered chemicals either, just the sun only.
Maybe once or twice per year, I will bring to SLAM level and allow levels to drift down just as a cleaning session. My FC levels have always stayed within the parameters of the CYA/FC relationship prior to the SWG. On average, over 5 months each year, I would say my levels have been maintained at around 5.5 ppm and nothing lower with 60 CYA. This is the average of the 20 weeks that the pool was opened. The extended testing is done weekly.
Liner fading progression after 3 years
I feel Dave has hit this on the nose. If you can provide us data, that would be great. A few items that you failed to mention is how long have you had the pool, how old is the liner, and are you the only owner? If you purchased the home from someone else, there is not enough information. Fading becomes more noticeable each year after the first few years. One would assume that after 7-10 years, the progression is a lot faster.
I have already drained the pool and they are replacing the liner today, so I can't do a test. Haven't done a test in the past month simply because I knew I was about to replace, and the kids had quit swimming for the summer. However, my CYA was around 50-60 all summer, and I would says i've kept it there for the past few years since I started TFP method. I've tried to keep my FC above 5ppm during swim season, which typically requires a gallon of 8.25% bleach per day during the sweltering months (south Louisiana). I pour it straight into the side of the pool in front of the skimmer. I wish I had taken some photos - they replaced the liner this am. But with water in it, it looked almost completely white. Once they drained it I could still see a faint amount of liner color/designs throughout.
My pool does indeed get most day to all day sun. When I bought the home 4.5 yrs ago, the liner had been in the pool for a few years already, however it didn't show any signs of fading. The previous owner used pucks only (via a feeder off of the filter), which is what I used for probably a year or two before I learned about TFP. I had a couple of really bad algae outbreaks (which is what led me to TFP) so I has shocking the heck outta the pool using granular shock, which likely led to a fair amount of the degradation. So it's unfair to say the bleach caused it, although as I said before I did do a few really hard/long slams when I first go started and was still trying to figure it all out. However I've noticed the degradation more and more each year even using TFP.
I was really just wondering if anyone had a consensus on what levels of FC would start to cause faster degradation. I guess it's fair to say that doesn't exist, and to just stay within the TFP guidelines? Thanks all for the honest and quick replies.
My pool does indeed get most day to all day sun. When I bought the home 4.5 yrs ago, the liner had been in the pool for a few years already, however it didn't show any signs of fading. The previous owner used pucks only (via a feeder off of the filter), which is what I used for probably a year or two before I learned about TFP. I had a couple of really bad algae outbreaks (which is what led me to TFP) so I has shocking the heck outta the pool using granular shock, which likely led to a fair amount of the degradation. So it's unfair to say the bleach caused it, although as I said before I did do a few really hard/long slams when I first go started and was still trying to figure it all out. However I've noticed the degradation more and more each year even using TFP.
I was really just wondering if anyone had a consensus on what levels of FC would start to cause faster degradation. I guess it's fair to say that doesn't exist, and to just stay within the TFP guidelines? Thanks all for the honest and quick replies.
Call the township to see when the final CA was approved. This will give you an idea how old the liner is. In addition, you really can not gauge what the previous owner did and how he/she took care of the pool. Most liners (from what I have seen), whether bleached out in certain spots from bad chemistry or not, usually go between 7-11 years before they shows true signs of real fading. Come back to me in 3-5 years and you will have at least a history of my liner and its progression. If you comment on the thread, you will be notified next year when there is an update.
Please post up some pictures of the pool and the new liner. Everyone here likes pictures!
- - - Updated - - -
I would say that this is not enough time to properly gauge if chlorine is a culprit or not vs. the sun & chlorine. If the person did this over 12 months inside, that would be a better experiment. If would not take much, just enough to test every few weeks to keep the chlorine at higher levels.
Please post up some pictures of the pool and the new liner. Everyone here likes pictures!
- - - Updated - - -
I would say that this is not enough time to properly gauge if chlorine is a culprit or not vs. the sun & chlorine. If the person did this over 12 months inside, that would be a better experiment. If would not take much, just enough to test every few weeks to keep the chlorine at higher levels.
I'd be interested in seeing what liner pattern you have and who the manufacturer was. Mine has significant fading too and mine is from Merlin Industries.
https://www.troublefreepool.com/threads/171725-Liner-Fading-Fast
https://www.troublefreepool.com/threads/171725-Liner-Fading-Fast
Here is the link. They didn't maintain chlorine levels, but not sure it would need to be if in a sealed / cool environment. Obviously not the best test case as they knew it wasn't really scientific, but it is something.
https://www.troublefreepool.com/thr...-Vinyl-Liner?p=1373709&viewfull=1#post1373709
The test was done with no CYA and high chlorine of 20 ppm (Big difference). I really think that even if you kept your levels at the bare minimum all the time (even 2-3 ppm) with a CYA of 30 and monitored everything, no matter what you would get maybe 2 years extra between color fading. And what do you do if you have a big party? You have to add extra and test afterwards and add extra because no one wants to SLAM a pool.
As mentioned previously, my averages were 5.5 ppm, with CYA throughout the 5 months. Even if my averages were 4.5 ppm over the years, the fading would probably be less, but not anything one can really pin point. Keeping FC levels at 3 ppm constantly on average is almost difficult, if not impossible unless no one uses the pool.
The type of dye/ink used to print the liner makes a lot of difference. Organic inks and dyes will fade faster than other types. UV exposure plays a role as well. If the area above the waterline was just as faded as the area below, then I would think organic inks/dyes or UV exposure would be the main cause.
I would be very surprised if organic dyes are used for printing pool liner vinyl. The print industry continually goes through considerable change, so UV cured-pigmented ink and pigmented Latex ink would be my first guess. Dyes are much smaller molecules than pigments and dyes have a flat sharp shape. As such they are both quite water soluble and fugitive - meaning they fade quickly as they have more surface area exposed to UV [the sun]. Pigments on the other hand are larger round molecules. Even if pigments are larger, their round shape means less surface area is exposed to UV radiation. Even so, no pigments can last forever in an outdoor environment.
Unfortunately medium to dark ultramarine-blue is the most susceptible to sun fading and these colour tonnes are quite popular with pool owners.
Trichloroisocyanurate - stabilized chlorine [trichlor] can be quite hard on this favoured med-blue shade colour. Dichloroisocyanurate [dichlor], calcium hypochlorite, sodium hypochlorite [liquid chlorine] are less severe, but they too will affect colour over time, especially at high levels and if improperly dispersed.
Slowly poring liquid chlorine in front of a return - preferably in the deep end is the safest way to dose the pool.
Instead choose, white, light blue, turquoise, or royal blue. These colours resist fading, although eventually....
In the end it is better to have healthy water. Unsafe water may make your colours less prone to fading but I prefer a little fading.
Unfortunately medium to dark ultramarine-blue is the most susceptible to sun fading and these colour tonnes are quite popular with pool owners.
Trichloroisocyanurate - stabilized chlorine [trichlor] can be quite hard on this favoured med-blue shade colour. Dichloroisocyanurate [dichlor], calcium hypochlorite, sodium hypochlorite [liquid chlorine] are less severe, but they too will affect colour over time, especially at high levels and if improperly dispersed.
Slowly poring liquid chlorine in front of a return - preferably in the deep end is the safest way to dose the pool.
Instead choose, white, light blue, turquoise, or royal blue. These colours resist fading, although eventually....
In the end it is better to have healthy water. Unsafe water may make your colours less prone to fading but I prefer a little fading.
Great info thanks. I learned that I need to start pouring the chlorine in front of the deep end jet. After filling and CYA/CL add I've got my CYA at 30-ish right now and FC at 5. PH is 7.5 and TA is 140. Just got our first cold snap so plan on dropping run time on the pump down to about 6 hrs/day. I keep the pool "open" all winter although it won't be warm enough to swim until late April.
Your PH looks good. I am wondering if you experience PH rise due to your TA being at 140. Thanks!
Sorta wondering the same. Guess our tap water is alkaline. Wondered if I needed to try and bring it down some but will likely wait until spring. It's still technically within the limits.