Question on the process of doing an AA treatment for Iron Stain removal

[jesse-99]

I'm asking regarding this link specifically: Ascorbic Acid Treatment - Further Reading

I have some iron staining I want to get rid of while the pool still has water (instead of a light MA wash at year's end/beginning) so I'm planning on taking FC down real low and adding about 1.6 pounds of AA (just purchased from here: Amazon.com: PC NetwoRx Pure Ascorbic Acid (Vitamin C) Powder (1 Pound) : Health & Household)

Step 4 says the following:
Put the filter on RECIRCULATE if you have a Multi-Purpose Valve(MPV) on your filter. If you have a cartridge filter then remove the cartridges.

... but I would rather leave my Cartridge filters in place (I have both a 100sq ft and 400sq foot cartridge filter, each on different pumps) so the iron actually gets OUT of my pool, along with adding PolyFill in my skimmers. I just don't want to have to worry about whether the iron is Solution or in Suspension based on FC levels in the future, or worry about sequestrants, etc. I just want it totally gone and collected up by the filters and poly-fill.

EDIT: as my follow up post below states, MAYBE the purpose of removing the filters for a bit, is so the AA doesn't get stuck in the filters? and instead can do its' magic in the pool itself?

I'm assuming, its OKAY to leave my my Cartridge filters installed, despite what step #4 says, if I want to remove the iron completely? I also assume where the steps say to run your filter for 30 minutes, that I don't have to STOP filtering after 30 minutes, LOL. (it's worded as if you're not supposed to filter longer than 30 minutes and just stop filtering, but I think it's actually inferring to filter for at LEAST 30 minutes afterwards, for circulation).

Anyways, just looking for some input on keeping both my filtered in place during this process. (@IceShadow)

 

[jesse-99]

-delete-

 

[jesse-99]

Just bumping this one... I'm wondering, MAYBE the purpose of removing the filters for a bit, is so the AA doesn't get stuck in the filter? and instead can do its' magic in the pool itself? (no idea)

Anyone have thoughts on this? Some posts about this treatment mention to remove the actual filter(s) during this process, others don't even mention that and just tell you to run your filter. So I'm wondering the reason as to why or why not to remove the filter during the AA treatment? (again keeping in mind my goal isn't to put the iron back into Solution, but keep in in Suspension so I can remove it from the pool)

 

[mknauss]

The AA wiki describes how to remove the staining then sequester. You wish to remove the staining and remove the iron. Best way to do that is to drain and refill the pool with iron free fill water.
But if you are going to try and filter out the iron, leave the cartridges in. Be sure to clean them of the iron as it oxidizes.

 

[jesse-99]

Can't do a drain and re-fill. So yeah, I'm using the combination of poly-fill in all 3 skimmers, and regular filter cleanings. Thanks for the response!

 

[mgtfp]

Further down in the article (under "tips") it says:

• Putting the filter on recirculate or removing the filter cartridges helps avoid the small chance of coating your filter media with metals, which might end up forcing you to replace your filter media. This doesn't usually happen, even if the filter isn't on recirculate, but best to avoid even the small chance of a problem by using recirculate or removing cartridges.[12]

 

[jesse-99]

I have my Absorbic Acid and picked up 4 bottles of Jacks Magic Purple Stuff (sequestrant) as well as I figured I'd try after the AA treatment it since there's only a month left in the season anyways and I have most of the iron filtered out of the pool (at least the iron that didn't stain the plaster) . I plan on doing the AA treatment on Thursday. Just have to secure some Algeacide quickly (hopefully today/tomorrow) for when my FC gets low (starting to lower it today). Will try to show some before/after results. My disappearing edge basin (1500'ish gallons) is heavily iron stained so we'll see how that turns out, as well as some other areas in the pool.

 

[jesse-99]

Quick question.

Since I have to takea my FC way down to perform this AA treatment, 2 choices:

** Option #1 - Use NO Algaecide
** Option #2 - Use the ONLY available Algaecide I've been able to get on-hand which is Copper based (and go LIGHT on the addition instead of the amount as specified)

I'm doing this tomorrow (can't put it off due to timing of other things).

Which of the 2 choices would you go with? (Yes, I tried getting Polyquat 60 but, nobody is stocking them with reasonable shipping times, and this has to be done tomorrow)

Thanks!

 

[mgtfp]

Both choices don't feel really appealing. #1 bears the risk that you have to slam afterwards, which bears the risk that you oxidize any remaining metals and bring back the stains straight away. And same applies kind of to #2. I don't know effective these copper based algaecides are to start with, and with lower dosage you are back to #1 plus some added copper.

I feel, an AA treatment is something that should be done right or not at all, I wouldn't make compromises on that one.

How about waiting until the water is a bit colder?

Let's see what @mknauss thinks.

 

[mknauss]

Wait. Iron is not harming anything. Best to do it with cold water and when you can replace the water with iron free water.

 

[jesse-99]

Yeah I know neither is exactly appealing, ha, that's why I'm trying to pick between two non-ideal situations. (sometimes I we just can't wait for everything to be perfect!) I'm leaning towards proceeding with some Algaecide, since I'll be using a sequestrant after, I'm hoping that'll negate any of the copper from the algaecide, since I'm only going to be open another month or so anyways before closing. It's not like I'd be without chlorine for days, we're talking a a day at most and using the algaecide to get by... But yeah I get it. Sometimes there's gray areas. this is one I think. Appreciate your input !

 

[jesse-99]

Wait. Iron is not harming anything. Best to do it with cold water and when you can replace the water with iron free water.

Unfortunately that's not really an option cause a re-fill isn't happening until start of next year's pool season in May. (The only way to get iron free water here is trucking it in, since I'm on a well, draining is pointless, and I don't want to pay $2800 for water for a measly 4-5 weeks of pool operation the rest of the season). It's not ideal, I know.. that's why I'm asking to pick from the 2 scenarios presented if you had to. (I'm leaning towards option 2) Thanks!

 

[Katodude]

So when I did my AA treatment I left the filters in. I would also recommend that you wait a while until the water is colder. Do it right before you close, and close late. If you can wait until the water temp is in the 50’s that would be the best. I tried putting Polyfil in my skimmers and that did not work. However, what I did do hoping it would work is poured LC right into the skimmer hoping to precipitate the iron and have the polyfil catch it. It did not, but the filter ended up catching the iron. A quick rinse of the filter after cleaned it right up.

If I were to do another AA treatment, I would filter the filters up with Polyfill along with the cartridge. Then pour the LC again right into the skimmer then dump the Polyfill and the clean the cartridge.

Again, this worked for me, but YMMV.

 

[jesse-99]

Did the AA treatment this morning. Like I said, due to timing of other things with the pool and real life on-goings this was the only day I could tackle it. Few notes...

• I ended up using a copper based algaecide since I could not get Polyquat 60 in time. Couple of reasons why:
  • I wanted some protection against algae when I did this due to keeping FC super low.
  • I'm using a sequestrant after the AA application so any copper staining should hopefully be minimized
  • I'm only open for only 4-5 weeks before end of pool season anyways.
  • This was the -only- time I've ever added copper (my fill water is copper-free (and tested at a nearby lab), so I'm doubting a one time dosage of copper algaecide is going to cause me huge problems I'll regret
  • My pool guy (who I trust because he also follows TFP here and has -earned- my trust to date) has tried both copper algaecide and Polyquat 60 over the years and his personal experience is that the copper based products have provided better protection against algae than copperless products like Polyquat 60 (that's just his -opinion-, I am NOT stating fact, please don't jump on me for this).
• The absorbic acid treatment was very easy to apply and sprinkle in the pool. I tried to focus on adding it to areas that were more heavily stained.
• Staining removed very quickly and the results were remarkable to watch
• Used 12 ounces of algaecide
• Used 3 pounds total of absorbic acid (I think I could use have used another 1 pound)
• Used 3 quarters of Jack's Purple Stuff after the treatment
• Kept my cartridge filters in place (maybe give them a good cleaning in a couple days)
• I started with pH of 7.4, and it went to 7.0 after the AA treatment
• I started with TA of 70, and it went to 60 after the AA treatment.

Here are some quick pictures of a couple of the problem spots, with before and afters.

Before #1


After #1


Before #2


After #2


Thanks to all who chipped in on the advice... and whoever put together this page as well: Ascorbic Acid Treatment - Further Reading

 

[mgtfp]

These certainly were some ugly stains, and the AA did a great job. Keep us updated how you're going with the sequestrant, curious how that works out long term.

 

[jesse-99]

Will do.. I just bought another 4-pack of Jack's purple. Those stains were just -SOME-, there was a lot more, LOL. But so far, the difference is amazing. I'd wager to say that 80% of the staining is removed in the first 30 minutes... another 20% has improving over the last 6-8 hours... but the bulk of it is definitely up front. Very happy I did this, it's a HUGE difference. I'm bringing up FC, very slowly at this point as well, just to get some in the pool.

 

[jesse-99]

Just a quick update.. Everything going well. AA treatment very successful from 5.5 days ago. Only area it didn't do the trick is in the cave grotto which I sort of expected because the water movement is more stagnant in it, and I'll likely have to do another AA treatment with dropping the AA in the grotto when I'm physically in there myself, but that's a minor thing for the future. I am 100% pleased with the results of this entire treatment more than 5 days later. I'm on the Jacks Purple Stuff maintenance plan now (roughly a quart per week) which isn't cheap but will get me through the next 4-5 weeks without the iron going back into suspension I think and restaining my plaster.

Re-balancing was pretty simple. LC would get eaten up pretty quickly, and it -seemed- like the first 1-3 days I had to double the amount of chlorine to get to the target chlorine I wanted (I was only targeting like 2-3 FC the first four days or so, since I still had algaecide in the pool to help with algae. But we're close to back to normal again with everything and very very happy with the pool and results.

Would highly recommend this treatment of AA and Jacks Purple (or Blue) stuff to take care of bad iron staining. Huge thumbs up.