Stains respond to NOTHING

[orthofish]

Hey y'all. Haven't posted in awhile but you probably knew I would be back A few years ago I noticed a couple of stains in the shallow end. They did not respond to Vit C nor pucks. With my pool surface I was the only one who noticed so I let it go. Probably should have added a sequestrant but that's hindsight Last year I noticed more and some on the side close to the shallow end return. Thought, O.K. better put a stop to this Knowing they didn't respond to either of the above mentioned I tried the AA treatment anyway. This was Wed. 4.5lbs AA, 18 oz. Poly 60. Nothing happened. Didn't even lighten them. I added 2 quarts of sequestrant Thurs. evening. Held a cut lemon on one of them for 30 mins this a.m. NOTHING. If is is cobalt staining, what will get rid of them?
My #'s this morning:
pH 7
Cl 0
CH 200
TA 50
CYA 40
Salt 2420
Temp 70

 

[orthofish]

Here are some pics of the stains

 

[JoyfulNoise]

You might want to consider using Jacks Magic StainID Kit.

Why would you think it was cobalt staining??

 

[orthofish]

One winter I let my CH get down to around 100. Maybe poor gelcoat? Just not sure why they wouldn't respond to Vit C nor the puck?? What would the stain kit tell me that I don't already know? They feel rough compare to the rest of the pool surface. Almost like hardened tar is the best way I can describe it.
Thanks for the reply Matt

 

[JoyfulNoise]

It will help to differentiate between organic stains, iron & cobalt, copper and calcium scale. Once you know which it is, Jack's Magic has a variety of different chemicals to help remove them.

See here - http://www.jacksmagic.com/pdfs/Stain-ID-Kit.pdf

 

[orthofish]

But wouldn't the AA, lemon, or puck at least made some sort of difference if it were any of those stains????

- - - Updated - - -

I think I've read every thread on here about stains:cyclopsani: Seems most get results with citric acid or pucks. But noooooooooo, not me.

 

[JoyfulNoise]

Old copper stains that have converted to CuO are very difficult to remove with either AA or citric acid. By the way, a lemon is only going to have a very small amount of citric acid in it, hardly enough to be useful.

 

[orthofish]

Is it possible to remove them(if it is old copper) or is this something I will have to live with and continue to use sequestrant?? Didn't know that about lemons. But crushed vit C in a sock didn't budge them either.

 

[orthofish]

Another question. Will the sequestrant affect my CH #'s??? BTW. My numbers are usually spot on according to TFP. These #'s are just because I'm dealing with these dang stains. I've always had a pH of about 7.6. Should I try to keep that down some due to the staining? If so what??

 

[pooldv]

Try putting a vit C tablet on the stain for a couple or few hours and see what happens. For 11 or 12 bucks I agree that the Jacks stain kit is worth a shot.

 

[orthofish]

Thanks. I will give it a try and get the kit.