Finish coming off liner

[IronMan13]

All,

Can anyone tell me what I have wrong, chemical wise or other, that would cause the finish to come off the liner along the water line?

It's happening in 2 corners of the pool, in the past we had waterline scum problems we've tried to clean off and caused some of the finish to rub off, but it wasn't this bad when we closed it last fall. When opening this spring it looked like the attached picture. Not sure what I did wrong that would cause it to be this bad.

Thanks!

 

[Texas Splash]

That is odd. There have been some cases where the quality of the liner simply wasn't up to par. The test logs in your APP appear to be fine. It appears the pattern is coming off at the normal summer waterline correct? Or was that the winter/closing waterline?

Did you close the pool, or did a company do it for you?

 

[Gotta Pool]

Do you have a pool robot?

 

[IronMan13]

That is odd. There have been some cases where the quality of the liner simply wasn't up to par. The test logs in your APP appear to be fine. It appears the pattern is coming off at the normal summer waterline correct? Or was that the winter/closing waterline?

Did you close the pool, or did a company do it for you?

It's both the winter/closing water line and the summer waterline. We have an auto cover so we don't drain it any when closing. This past winter was the first year I closed it myself.

We've had all kinds of issues with this liner, it started wrinkling horribly within the first year. The company, Latham, agreed to give us a new one but didn't admit any fault. From online groups/sites we were told it wrinkled because our chemicals were off/we cooked it because we would leave the cover closed 24/7 when not using it/on vacation.

We did start to wear the finish off when attempting to clean the stains off the liner at the waterline, but it didn't look like this when we closed.

We haven't installed the new liner yet as we figured even though this one looks terrible it's still functioning so let's keep it in until it gets too bad then replace it.

That being said in the mean time I'm trying to figure out what, if anything, I did wrong to cause all our issues so I don't repeat those mistakes. Or confirm we just got a Crud liner and wasn't our fault.....

 

[IronMan13]

Do you have a pool robot?

Yes we do, but that particular spot is in the tanning ledge so the robot doesn't go there ever because it's not deep enough for it.

 

[Texas Splash]

We have an auto cover so we don't drain it any when closing. This past winter was the first year I closed it myself.

The only thing I see in your Poolmath logs that "might" (big stretch perhaps) be a contributor could be the elevated pH a few months ago coupled with a higher FC, perhaps during closing prep. That along with the cover maybe. I'll ask @JoyfulNoise for his thoughts.

Do you remember last fall, did you lower the pH as part of your closing? The logs don't show it. Do you recall the number? I'm assuming you increased the FC as well?

 

[JoyfulNoise]

That’s probably where the cover is rubbing against the liner when it’s closed. The cover will not perfectly fit and so there will be areas of contact and non-contact all around the pool. The areas you are seeing are probably where the cover has the most contact with the liner. Also, keeping a pool closed with an auto cover all the time will cause problems with the liner because the small air space that is there is always hot and humid. That’s going to cause the vinyl to swell a bit and probably induce wrinkles.

Autocovers do solve some problems but create others as well. Not sure there’s much of solution other than to expect more frequent liner replacements with your pool setup.

 

[Gotta Pool]

OK, I was going with the robot because it looks like mechanical damage. That same sort of damage could be caused by the pool cover, so I, too, am going with that as the most likely cause.

 

[JoyfulNoise]

If it were the robot, you’d see it more evenly across the entire water line if the pool. Also, you should be using a robot with foam rollers to ensure that there is minimal damage to the liner.

 

[Gotta Pool]

Probably, but the OP only posted a small section of liner and has yet to divulge the type of rollers employed. Your point., however, is well taken.

 

[IronMan13]

@Texas Splash @JoyfulNoise @Gotta Pool apologies all for the delay getting back to you and thanks for all the input! I did not record my readings right when I closed it. I see in my logs my last reading was in september but i didn't close it until into october. I know i checked it and chlorine was probably above 10, but i didn't record it into the app. the water level when i closed it was right at where the waterline/wearing off is, which in reference to the skimmer is right at the top screw of the 2 screws you keep the water level between.

I've added some more pictures for reference. based on the location of the wearing I don't think its the auto cover rubbing on it. You can see here that its basically the corner where the cover closes too so the cover doesn't even come close to where its wearing. robot is the Dolphin Nautilus CC Supreme

Also its wearing in the other corner, same side of the pool (hard to see in this pic, but you can see the white area right at the water line in the corner)

and on the opposite side of the pool, no wearing off at all, its like this across this entire side


I as going to make a larger post about this but since I mentioned it above and its already been touched on, I'm really just trying to learn what, if anything, I did wrong on this liner so that when we swap it out with the other one we have, I don't make the same mistakes again. Here are some additional pictures of the wrinkling as well as some kind of sediment/dead algae that never seems to go away....



So if i had to summarize what I've learned so far as a "do/don't do on the next liner" it would be

• open the cover to let the pool breath - we've started opening it daily and also leaving it open while on vacation. what would you say would be the max hours/days to leave it closed for and not cause any issues?
• don't let the water get too hot, it has gotten up to 93+ in the past, again what would be the max temp to not cause issues?
• balanced water - with regards to the different readings, which one would have the most impact on the liner? ph? chlorine? combination?
• don't use magic eraser to clean the waterline gunk
• don't use sunscreen with avobenzone in it - we've read this contributes to the build up on the water line
• test my water daily and adjust the SWG output as needed - I'll admit I was terrible at this initially, I'm trying to do better this year. I was under the wrong impression that having a SWG I could set and forget. This lead to wild swings in chlorine over the past 4 years due to it getting to low and water becoming cloudy to then SLAMing until it was clear again and over compensating by running chloring at 13-15 for long periods of time

any other lessons learned I should add?

thanks again for everyone's help!

 

[Texas Splash]

what would you say would be the max hours/days to leave it closed for and not cause any issues?

If you could pull it back for an hour or two each day I think that would be good. If not each day at least every other day. It also allows the sun to cook-off any CCs trapped.

what would be the max temp to not cause issues?

Matt may have a more scientific answer for that one. Our water in south Texas can easily fell like bath water at ~95 degrees, but I don't use a cover.

don't use sunscreen with avobenzone in it - we've read this contributes to the build up on the water line

I've not heard about that specific ingredient before, however we use very little lotions around our pool and still get a small black scum line in a corner or two once or twice a year. But if you find that avoiding that product/ingredient helps, that's great.

test my water daily and adjust the SWG output as needed - I'll admit I was terrible at this initially, I'm trying to do better this year.

Guilty as charged. We all do this. "I'll test it tomorrow", then tomorrow comes and we say, "I'll get to it the next day". Ugh.