AA treatment questions

[LivinMyBestLife]

Hi all,
I have a 3 year old Pebble Tec Pool and have been waiting all season for my pool guy to do a Jacks treatment on what I believe are Iron Stains. He is clearly not coming, so I think I need to do an AA treatment myself and then get the water rebalanced before closing in a few weeks (I'm in New England so I need to close soon). Last year at open, there was waterline brown staining, and it is still there. I really want to clean it up before closing again so that it is not worse in the spring.
I have a Nature2Fusion Soft. I believe the original (3 seasons old) mineral cartridge is in there. I have never touched it. My stains are light brown and lift easily with AA though, so I dont think they are copper/silver from the mineral cartridge. I think they are Iron. Here are my questions...
1.) I don't think I have a "recirculate" mode. I have a cartridge filter. Do I just remove the cartridges and turn the pump back on? How long do I keep the cartridges out during the AA treatment? Put them back when the stains are off and Metal Magic is in? 24hrs?
2.) The water will still flow thru the Nature2 and the heater - I don't see a way to bypass. Do I need to get those metal balls out of the mineral cartridge if I am running AA treated water through it? I have read the page about how to do it... just a little afraid to start intentionally breaking things open -.
3.) Is the heater ok to have the treated water run thru? I dont see any way to bypass it. (Pentair MasterTemp Gas heater)
4.) Should I remove the salt cell, or let the acidic water run through it? How do I remove the cell, and can the pump still run with it out? I have never cleaned it (3 seasons), so maybe the acid wash would be a good thing?

Any TFP pros in Boston?? I clearly need a more responsive pool service company, or a mentor! I am a rookie and afraid of breaking my pool!

Thanks!

 

[Texas Splash]

Hello! Yes, you'll remove the cart filters as noted in the link below. That page really outlines the AA process quite well. The heater and cell will be fine. An AA is different and not aggressive like an acid wash done by adding a large amount of acid to lower the pH really low. Your AA treatment should go relatively quick, so just keep those instructions handy so you can refer to them. Good luck!

Ascorbic Acid Treatment - Further Reading

www.troublefreepool.com

 

[LivinMyBestLife]

Thanks! I have studied the instructions and feel mostly ready! I do have a couple more questions....
1.) My pool has a raised beam covered with a stone veneer over which the spa spills over. The bottom of the stone veneer sits just below the waterline, so the stones are partially submerged. Do you think the stones are the source of the iron? My home Taylor Kit does not test for metals, but every pool store test I have ever done shows none or trivial amounts of Iron and other metals in the water. Yet clearly there is some Iron that plates out, probably when the pH creeps up or if I SLAM. (The pH is a constant battle due to the salt generator and aeration of the waterfall - I am wondering is an acid feeder is in my future) The staining isn't bad, but there is a mild brownish discoloration to the pebble tec and in a new pool, it drives me nuts.
2.) Any worry for the stones themselves getting a bath in ascorbic acid? It is a weak acid so maybe I should just expect it to descale and clean them a little? Just wondering if I need to be worried about it bleaching them out or anything? Or leeching even more Iron out of them into the water and making my problem worse?
3.) If I add polyquat 60 before I start, is it going to throw off pH readings (Taylor kit) and confuse me when I try to bring the pH back up? If the water is 64 degrees and falling do I even need the polyquat? Chlorine had been sitting around 7, now at 4, waiting for it to fall before I start... so no reason to think there is Algea looming. I've read on here that Polyquat messes up pH testing.
4.)Hoping to close as soon as I get the stains cleaned up and the chemistry back to normal, maybe in 3 weeks or so. I assume I should add extra Metal Magic before the close? My pool guys will superchlorinate at close - is that going to cause staining all over again? Would it be better to close as-is (plus extra Metal Magic) and do AA in the spring? I am just hoping NOT to open with brown waterline staining this spring.

Thanks for you help and support - I learn so much on here!!

 

[Texas Splash]

I wouldn't think the stones have anything to do with the iron. I don't think we ever confirmed .... are you on a well? In any case, the stones should be fine. I would follow the AA link steps for best success. As for the closing super-chlorination .... that could result in a reaction to iron suspended in the water. Just depends on how much chlorine is added and the iron content in the water. Next year talk to us about ways to potentially filter iron from your pool. Might be worth trying next season.

 

[Phookinl]

I can understand that iron would be an issue in well water. I would have expected it to drop out very quickly at pH7 - pH8 and in an oxidising environment.
There are other things that cause brown stains. In the absence of something to complex the iron and keep it soluble, I wouln't expect to see more than a small fraction of a ppm in solution above pH4. Are chelating agents commonly used in the US ? I could see a bunch of complications around managing water testing if there are chelating agents in the pool water.