Liner fading from FC?

[Tie Twist]

That is the pattern of my old liner, which was 12 years old. I woud say it was about 40% (at most) faded. I didn't realize just how dark it used to be until I compared it to a sample when we too kit out (I moved in to he house 3.5 years ago).

The new liner is Blue Mosaic.

 

[Tie Twist]

Update to this thread. This spring upon opening I saw no evidence of fading. (?!?)

I don't really know what happened. Kinda embarassing...maybe the liner under water was cleaner or something, I don't know. But I have to conclude that there was no fading after all.

 

[chem geek]

So if someone sees a difference in color above and below the water, then perhaps they need to do a test of temporarily lowering the water level to see if there is really a water line visible with different saturation above and below. Anyway, good to know that your experience is in fact consistent with what others report which is that most liner fading is from sunlight and time so occurs both below and above the water line and is not usually due to chlorine. There still may be the exception with the medium blue organic dye that is chlorine sensitive and will eventually fade more in the water than above.

 

[Yev]

Tie Twist, what brand of liner do you have? CUrious to know if it is a high end brand or a lower end brand.

 

[duraleigh]

Tie Twist, what brand of liner do you have?

30 Gauge Vinyl Liner. Liner is manufactured by Latham. Blue mini tile design. (like a three tone blue coloured tile pattern) pretty common / standard pattern.

xxxx

 

[BobbyR]

Liner fading is the one concern I have with the TFPC method. This is my second year running my pool this way and my liner is badly faded below the water line. It was a very dark blue and black tie die pattern and it is now very light blue. The narrow strip above the water line has retained its original colour so the bleaching is very obvious when the water lever falls. The liner had faded prior to starting TFPC but it is much worse now. I suspect the problem results from once daily chlorination vs continuous feed. The spike in the FC level after adding the bleach may be what leads to fading. I am not really concerned at this point because my liner is already 12 years old but this will become more of an issue when I replace it. I'm guessing the fading shows less with a lighter coloured liner than with a dark one so maybe that's what I'll go with. I suspect this is just the price you pay for perfectly balanced, crystal clear water.

 

[chem geek]

Look at this post I wrote earlier in this thread. Many colors using inorganic dyes are impervious to fading from chlorine. It's the medium blue color that uses an organic dye that is susceptible to fading from chlorine.

I think it isn't just the dosing variation that has the chlorine level swing, but that even the minimum FC level is set to prevent algae growth regardless of algae nutrient level and usually people using Trichlor before finding TFP aren't at that level and are lucky enough to have lower algae nutrients. Between these two factors, their average chlorine level may be half or less so would fade the liner about half or less as fast.

You can use supplemental products for algae prevention and then target a lower FC/CYA level, but this is an advanced technique not taught here for newbies. We also haven't worked out the precise level trade-offs, but I can tell from my own pool after it had phosphates removed in an experiment that the FC/CYA level can be very low and not have any noticeable algae growth nor chlorine demand from such growth so the issue is more about having enough chlorine to oxidize bather waste and still having a high enough level for disinfection. Cutting the levels down by half that of SWCG levels would be reasonable so in the 2% to 3% FC/CYA ratio range. Of course, the use of phosphate remover or weekly Polyquat 60 algaecide or other methods is extra cost, but this may be paid for by the lower chlorine cost over time. It all depends on your situation and would not work well at all if you were using HEDP metal sequestrants or had high phosphate levels in fill water with a lot of evaporation and refill. It is these complications that make the technique an advanced one and not simple (i.e. not "anyone can do this" sort of advice).