Stains on bottom of vinyl liner

[bdpeter]

I have these light goldish stains on the bottom and a bit of the sides of my vinyl lined pool. They don't brush off w the brush or pool robot.

They were there last year as well when I closed, and don't appear to be algae or growing . My FC is around 7-10, cc 0-0.5, ph 7.2-7.4, ch 100, cya 60. Temp 58-62.

How can I test if they're metal stains? If they are, Do I really need to bring the FC to 0 to get rid of them , or will they ever go away completely? Liner is about 8-9 years old.

Thanks

 

[duraleigh]

First step is to correctly identify the strain as organic or inorganic (metal). Crush up 10 or so cheap vitamin C tablets, put them in a sock and then hold the sock down onto the stain for maybe 3 minutes or so. If it removes it or lightens it significantly, it is a metal stain.

If that has no affect, try holding a tri-chlor puck directly onto the stain for about a minute and see if it has an effect. If it lightens or removes it, the stain is organic. Report the results back and we'll help you get rid of the stain.

 

[bdpeter]

Ok. So I did the Vit C test and it clearly removed the stains on side of liner, which are the same as ones on bottom.

I also read the AA guide, so it looks like that's what I'll need to do. Few questions:

Do I really need FC down to 0?
If so, what's the quickest way to get there? My OCLT only has me losing less than 1 PPM nightly.
Second, what is the best sequestering agent for vinyl pools - The Purple Stuff? Right now I'm BBB, but want to do this before I install my SWG
Should I put any "metal out" in now, or wait till after the AA does it's thing?

Thanks all,

Brian

 

[duraleigh]

Yeah, you'll want to bring the FC down...be patient it will get there. I am not a stain expert so I don't think I'll add any more other than to say "Jack's" products are a little pricey but seem to have a good reputation for performance.