Is this liner damage or stain??

[pedsrn]

Vinyl, SWG. Rails are oxidizing (planning to paint tomorrow), could it be from this? Today, I found this shown in the pic. Specifically, the white line is what I'm asking about, but any advice on removing the stain above it is also appreciated. There was a fine brown line over it, but it easily brushed off. This is ONLY on the side of the pool that gets morning sun if that makes any difference. Also, this is the typical water level line, I've just neglected the pool and found a leak today so it's a few inches low. Advice greatly appreciated! TIA!

PH 7.3
Alk 130

[mbar]

Can you give us all of your numbers? Can you scrape the line with your fingernail? The top of the liner looks like just dirt to me, with some algae mixed in. Especially since it is on the sunny side.

[pedsrn]

Thanks for your reply.

This morning's numbers drastically different. I added CYA and 2G bleach last night. I also added salt and ran SWCG 12 hours. I have an obvious bloom starting up. I knew this last night after stepping into the pool. Don't worry about my chlorine numbers (or lack thereof). I'll add some borax today and then shock tonight and get the water straight. I'm heading now to get patch stuff (glue dried out) so I can top the water off. My concern here is the white line.

FC 0
PH 7.2
ALK 80
CH 100
CYA Was low when the white line showed up. Not testing today because I just added some last night.

WHITE LINE: Can not scrape with nail. Almost feels like it is in the liner. Only on morning sun side of pool.

ALGAE/DIRT LINE: Been there since opening this year. Goes all the way around pool. Have tried scrubbing with bleach with no luck.

Much thanks!

[pedsrn]

Ohhhhhhh...something probably worth adding that MAY be the culprit. My dear son had some battery operated toys down by the pool. Yesterday, I found a corroded battery IN the pool.

[mbar]

I hate to be the bearer of bad news, but it does look like damage to me. I was hoping it may have been calcium build up, but I don't know of any white stain, especially one so even as that. Is it all the way around the pool? If it is damage, they sell borders that you could put on that would cover it.