Metal Magic Spot Chalk and stain identification

[LivinMyBestLife]

Does anyone know what is in ProTeam Metal Magic Spot Chalk?
I have some brown staining on my SWG PebbleTec pool... pool guy told me it was organic (from acorns), but no amount of shocking burns it off, and rubbing a chlorine puck on it does nothing.
The ProTeam Metal Magic chalk rubbed on the spot then brushed does seem to remove it... but there are too many spots for this to be a practical way to remove all of it.
I will try putting some Vitamin C powder on the spots next.
Anyone have any guesses if a chlorine puck doesn't touch it, and this Spot chalk does? ProTeam claims this product takes off organic and metal stains.
Would the liquid Metal Magic remove the rest of the staining if the chalk product works? Or does the liquid just sequester but not remove stains?
Also... when I take my water down to Leslies for a test, it comes up as having no metals (copper and iron)... not sure I believe it.
Attaching a pic of the stains...

 

[Texas Splash]

Does anyone know what is in ProTeam Metal Magic Spot Chalk?

The MSDS points mostly to trade secret (secret squirrel) stuff with some Ethanedioic acid, calcium and citric acid mixed in there. I'm guessing you might be leaning more towards iron. @JoyfulNoise might have additional info.

 

[JoyfulNoise]

Basically a grit stick that acts ask a mechanical grinder with chemicals added to dissolve metals. Of course it works, you’re basically mechanically and chemically dissolving a thin surface layer.

If the stain reacts to Vitamin C it’s iron and you can follow the standard AA treatment or try to spot treat it.

 

[LivinMyBestLife]

Thanks guys... Vitamin C will be here tomorrow and I will spot test.
Question about the AA treatment... is it okay to add the AA then run pump, circulating water through the salt cell and the heater? I will turn SWG down to zero and heater off, but I don't know how to bypass them, so I assume the AA treated water will still run thru all the equipment. Is this ok?
One more question about the AA treatment... I read all of the guidance here and it appears that people recommend liquid chlorine to raise your levels after AA treatment is done. What is the reason for using liquid? Just because it is fast? Could I use small amounts at a time of granular shock to bring it up (like 1/4 bag at a time for a 30k gallon pool). If it must be liquid... do I buy liquid shock? Or grocery store bleach? Same thing, just different concentration, right?
You guys are lifesavers... thanks for the help!

 

[Texas Splash]

Ideally you want the AA mixing around the pool only (filter bypass) so that the AA is not interrupted by filter media. The pH will only be low for about 24 hrs, so everything else should be okay, but be sure to follow the instructions carefully and increase the pH right away. We rely on liquid chlorine a lot because it's usually cheaper (or was - ha), is very efficient, and has next to no side effects like the others. I would use liquid in the beginning of your transition from AA back to normal, then once you're back to normal feel free to use any bagged product you may have.

 

[LivinMyBestLife]

So either liquid pool shock or regular bleach... whatever is cheaper and easier to find?

 

[Texas Splash]

So either liquid pool shock or regular bleach... whatever is cheaper and easier to find?

Exactly. They are the same main ingredient (sodium hypochlorite) just different % strengths. If you get laundry bleach, avoid the Clorox brand and never grab anything that says splashless or scented. Just regular/plain.