Mystery stains (vinyl liner pool)

[Sumosteve]

Hello! I am a long time lurker that finally made an account! Love this community and I have learned a lot from you guys.

anyways, I’m having an issue with some stains that have been multiplying in my vinyl liner pool. I thought they might be metal rust stains due to the orange/yellow color they have... but I tried the vitamin c tablet thing and they didn’t come up at all.

any idea of what I’m dealing with? I tried to take a couple pictures and have attached them for reference. As you can see there are a bunch of them around the drain. Another couple things to point out are:

- they are mostly on the deep end of the pool
- I test water almost everyday and try to keep everything perfect
- we do live around a fair amount of trees

how would you guys go about getting rid of these? When I try and “scratch” them, a little bit does come off, but it still leaves a stain on the liner...

thanks!

 

[AimeeH]

Welcome to TFP

I suspect algae. Can you share your most recent test results? Like this:

FC
CC
PH
TA
CYA

How you you chlorinate?

 

[linda1]

I'm dealing with the same thing. The spots really look like rust. Here is a thread I started in the above ground pool section.
Looks like rust marks

 

[toofast]

Hey guys I wonder if we have a new phenomenom going on..... we have some problems going out fiberglass but it looks almost identical to your vinyl issues

Little brown rust spots on fiberglass pool...

 

[toofast]

Hey guys I wonder if we have a new phenomenom going on..... we have some problems going out fiberglass but it looks almost identical to your vinyl issues

Little brown rust spots on fiberglass pool...

Little brown rust spots on fiberglass pool...

 

[Sumosteve]

Welcome to TFP

I suspect algae. Can you share your most recent test results? Like this:

FC
CC
PH
TA
CYA

How you you chlorinate?

hello, thanks for the response. Our levels are currently:

FC: 2
CC: .2
PH: 7.5
TA: 140
CYA: 35

i also attached another closer picture of what the spots look like.



- - - Updated - - -

Also, we use tablets and occasionally liquid chlorine to chlorinate.

The shock we use is called Pro team multi magic shock extra.

 

[Sumosteve]

I'm dealing with the same thing. The spots really look like rust. Here is a thread I started in the above ground pool section.
Looks like rust marks

Your stains look exactly like ours... Very frustrating, but I do feel like they are multiplying and want to figure it out sooner rather than later.

 

[AimeeH]

Sumosteve,

Your chlorine is currently too low for your CYA so again, I'm going with algae since you're low chlorine is an invitation for algae. Despite the others chiming in, I'm very suspect that these spots are algae, especially since you say the brush off.

Have you read up in pool school? Pool School - Pool School

 

[toofast]

There's no way in heck mine brush off.... I'm not so sure the original poster said his simply brush off I think he used the word scratch but he still sees it

 

[AimeeH]

sumosteve,

I'm still leaning toward algae. But.....having tried vitamin C tablet with no results, have you tried a chlorinating puck? Like dichlor to trichlor? Held on the stain or rubbed on it? If that clears it, again, more evidence of algae.

I have seen few and far between stains (not multiplying) in my own pool that appear to have been caused by the potential decay of a bright colored insect like a cow ant. They don't brush off and are rather bright red, very small spots and don't multiply.

 

[Sumosteve]

sumosteve,

I'm still leaning toward algae. But.....having tried vitamin C tablet with no results, have you tried a chlorinating puck? Like dichlor to trichlor? Held on the stain or rubbed on it? If that clears it, again, more evidence of algae.

I have seen few and far between stains (not multiplying) in my own pool that appear to have been caused by the potential decay of a bright colored insect like a cow ant. They don't brush off and are rather bright red, very small spots and don't multiply.

appreciate the input. We haven't tried a chlorinating puck. I will give that a go though and then let you know what we figure out. If it is in fact algae, how should we treat it?

As I said in the original post, we REALLY have to scratch at it for tiny bits to come off... it hardly scratches off.

 

[linda1]

appreciate the input. We haven't tried a chlorinating puck. I will give that a go though and then let you know what we figure out. If it is in fact algae, how should we treat it?

As I said in the original post, we REALLY have to scratch at it for tiny bits to come off... it hardly scratches off.

I've tried a magic eraser on my spots and it didn't do a thing. I've never used pucks so don't have any to try on the spot. I'll have to see if I can buy one to test with. I've used the TFP method since my pool was installed in 2010. Water has always been perfect.

 

[duraleigh]

Sumosteve, I suspect plain old algae as the issue, To start, your FC is too low for your CYA level. Have you looked at the FC/CYA chart and have you read "The "ABC's of Pool Water Chemistry" up in Pool School?

Do the stains brush away?

 

[toofast]

I'm just copying this from the original poster...

As I said in the original post, we REALLY have to scratch at it for tiny bits to come off... it hardly scratches off.