Under Water Vinyl Wall Stains

[CoffeeBean]

Hi,

I have a 16 X 32 AG vinyl Doughboy. Last winter I closed with shock & Polyquat. This spring I opened to pea soup. Once I got the water cleaned up and sparkling I could see a brownish greenish stain from where the winter water line was down to the wall/bottom angle.

I converted to the BBB method this year and spent the first 2-3 weeks in shock mode trying to see if it would bleach it away in case it was algae residue. Didn't phase it. I've tried brushing, using a scrubbie, etc., but nothing takes it off. It's below the water line so using anything on the sponge just washes away as soon as I dunk it in.

Over the summer I <think> that it has faded a little. It's more mottled in appearance than it was initially. It even might have disappeared from the top of the stain line down a couple of inches.

I use Ben's kit and, once I got the chems balanced, have been able to keep the water sparkling and clean.

I have read many posts that talk of Vit C, Jack's stuff, etc., but haven't seen anything related to under water stains in a vinyl liner.

I saw some that related to metal in the water but I don't have any way of testing for that and haven't seen any metal testing equipment in local pool stores.

I do have a heater but didn't run it at all last year. I have used it this last month or so.

I'm getting ready to close for the season (live in western PA. It was 40 degrees last night) so am wondering what I can do so that it doesn't get worse over the winter.

Any help gratefully appreciated.

CoffeeBean

[doggie]

I'm curious if you have a fiberglass step section. If so, did they stain too?

[CoffeeBean]

Hi,

During the winter I didn't have any steps in the pool. I take them out when I close up. This is an AG pool but I have a surround deck.

CoffeeBean

[doggie]

I'm thinking that you've got some metal staining happening. I've seen a few threads on how to get rid of those. Do a little searching here, you'll find the answers. (sorry, I don't have time at the moment)

[mbar]

You can test to see if they are metal by crushing up some vitamin C tablest and rubbing them on the stain., or use some ph down in a sock and rub it on the stain. IF the stain goes away with either of these, then it is from metals. Let us know how you make out

[CoffeeBean]

mbar,

Will this work underwater? I'm thinking that the Vit C or whatever will be washed away immediately upon immersion. OR will enough remain to use this as a test?

[waste]

I don't want to step on Marie's toes, but a small amount in a small area should indicate whether it's working.

[mbar]

Waste is right, you just need to put it on the stain for a while - you can even hold some in your hand and rub it on the stain. Ascorbic acid (vitamin C) will immediately lift the stain when it comes in contact with it. You will see a little clean spot where the vitamin c hits the stain if it is a metal stain. You can read through this stains and metals forum to read more about it. Feel free to ask any other questions you have

[CoffeeBean]

Well, I had a real "Aha!" moment when I put the Vit C against the stain. I came away clean as a whistle! That's why I love you all on this forum. I'd be totally lost about this pool without you guys.

An interesting thing also happened while I was in the pool trying out the vitamin C.

I have tried using a scrub sponge in the past with zero results. Today I accidentally brushed my foot along the coping edge and noticed that some of the stain came off so I tried the sponge on it.

I made my way all around the 16 X32 using my foot and the sponge (got lots of aquatic leg lifts in today!) and found that some of this stuff comes off down at the bottom of the pool. It didn't at all farther up the wall.

When I took the sponge out to look at it, there was rust colored stuff on it that rinsed out. Is this still metal too or do I have some algae?

[CoffeeBean]

I've been cruising the forum re: metal stains and see that I can order Ascorbic acid from a chemical company. I guess that beats crushing vit c tablets. Does anyone know how long it takes to get the stuff?

What happens to the water once all that ascorbic acid is introduced?

My numbers today are a little skewed since we've had a lot of rain recently:

FC - 6.5
CC - 0
TC - 6.5
pH - 7.3 or 7.4 (It's between the 7.2 & 7.5 marks on the container)
Alk - 100 (down from 120)
CYA - 30
temp - 82 F (I have a heater that keeps it at this)

What should I be doing first so I don't get things too out of whack?

Thanks.

CoffeeBean