Iron Staining // Ascorbic Acid Treatment

[Tiziano]

Hi there,

I'm a new pool owner and after getting a bunch of help in the forum I am doing an ascorbic acid treatment.

I have zero'ed out my chlorine with a combo of exposure and a little sodium thiosulfate. Brought pH down to 7.2 and have been following this thread. In addition, I am trying out one of these CuLator things to see if I can get the iron out of the water. Would love any advice on how to do that outside of emptying and refilling the pool.

So far so good! I have added a total of 1.5lbs of ascorbic acid over the course of the day. There are a few spots that seem to be a bit more stubborn and if there's any additional advice for handling these, I would welcome it.

Attaching a few videos to show progress. Can anyone help me set my expectations on how much of this will come off and where to call it quits? Thanks!

P.S. Big thanks to @mknauss for pointing me in the right direction!

 

[Texas Splash]

Time and water temp are your enemies right now. The longer you continue with the AA and zero chlorine in warmer water, the likelihood of getting algae which would require a SLAM and negate all the hard work. So as soon as you feel you have reached a good goal from the iron treatment, start the rebalancing process. If you find some stubborn areas remain, you might just need to continue with spot treatments.

Are you changing the water? If not, remember that iron is still there, so maintaining an optimum FC and pH are critical. As for the CuLator .... mixed reviews. Polyfill filtering can help when the iron is in a visible precipitating stage, otherwise, you'll be stuck with using sequestrants to keep the iron contained in the water.

Ascorbic Acid Treatment - Further Reading

www.troublefreepool.com

 

[Tiziano]

@Texas Splash I'm using Regal Algaecide 60. How often / much should I dose while I'm doing this? Water temp is 70-71. Is that warm enough for algae already?

I've got Jack's Magenta Stuff as a sequestrant.

I got some polyfill as well. Should I be waiting to put that and the CuLator (I have it at this point...) in the basket once I've put the sequestrant in? That's what I'm getting from the write-ups.

Also, I just realized I left my filter in my cartridge filter. Total rookie mistake there. I'll take it out now and just leave it cycling but has this filtered out the AA now?

 

[Texas Splash]

Water temp is 70-71. Is that warm enough for algae already?

It is, but if you are using an algaecide that should help buy you some time.

I don't think it matters when you use teh polyfill or CuLator. As for the filter cart, good question. Perhaps that's why some areas didn't quite react to teh AA like you had hoped? If you still have some AA, try pouring it on those remaining stains. Otherwise, slowly begin the transition back to normal once you feel you've completed the AA.

 

[Homebrewale]

What great timing. My pool equipment was just started this past weekend. I'm not chlorinating the water yet after sitting all winter. The temperature is 60F. I have Polyquat 60 available. I have rust stains in the deep end that are hard to treat individually. They were caused by a sloppy roofer who dropped some nails into the pool. I will be selling the house in July so I'd like to make the pool look good.

 

[mknauss]

@Tiziano Looks like you are having a good treatment. Let us know if that Culator things actual captures anything.

 

[Katodude]

So this is what worked for me.

I filled the skimmers with Polyfill and then I poured LC in the skimmer hoping to precipitate the iron and capture it there. That did not work. What happened was my filter ended up catching what I believe was most of the iron. Soooooo.

If I were to do this again, I would stuff my cartridge filter full of polyfill. Then pour LC into the skimmer.

Of course only do this if you have a cartridge filter and you are willing to risk ruining it and needing to replace the cartridge. And no promises it will work, it just seemed to work for me.

 

[Tiziano]

@Tiziano Looks like you are having a good treatment. Let us know if that Culator things actual captures anything.

Yea! Looking good so far. I left the filter running all night and being a bit ambitious put in another 2lbs of AA this morning. Also added 4oz more Algaecide. l will keep you posted on the CuLator.

I figure in about two hours I can put the sequestrant in and call it. I'm wondering if there's any advantage to letting the sequestrant circulate in the system and "grab" the iron before putting the cartridge, polyfill, and CuLator back in?

 

[Tiziano]

So this is what worked for me.

I filled the skimmers with Polyfill and then I poured LC in the skimmer hoping to precipitate the iron and capture it there. That did not work. What happened was my filter ended up catching what I believe was most of the iron. Soooooo.

If I were to do this again, I would stuff my cartridge filter full of polyfill. Then pour LC into the skimmer.

Of course only do this if you have a cartridge filter and you are willing to risk ruining it and needing to replace the cartridge. And no promises it will work, it just seemed to work for me.

Interesting.

So did you stuff the inside of the cartridge or leave the cartridge out and stuff the filter? I'll try this.

And I imagine if I do this, really I should be tossing the cartridge anyway because it'll be full of iron? Hopefully full of iron that is haha.

 

[Texas Splash]

I'm wondering if there's any advantage to letting the sequestrant circulate in the system and "grab" the iron before putting the cartridge, polyfill, and CuLator back in?

Remember that a sequestrant will bind-up and keep the iron in a water/soluble solution. So it might interfere with letting the iron get trapped by polyfill or other products.

 

[Tiziano]

Remember that a sequestrant will bind-up and keep the iron in a water/soluble solution. So it might interfere with letting the iron get trapped by polyfill or other products.

Oh! So should I not be using it? Or waiting until a certain (which?) point?

I'm going off the instructions in the thread I linked in my initial post, which says to use it but then again it's not talking about filtering the iron out. Advice much appreciated!

As a side note, will sequestrant work with Chlorine in the water?

 

[Texas Splash]

The AA articles are correct in recommending the use of a sequestrant quickly because they assume once the stains are lifted, the owner is going to start re-balancing right away. As such there is a potential for chlorine to aggravate the iron and we don't want the staining to reappear. But the articles can't address each pool owner's scenario. Once the iron is lifted off the pool surface, it MAY be available for filtration, but that depends on factors we cannot predict such as iron content and its propensity to be solid enough for filtration. It's a tricky deal - do I play it safe and bind the metals with sequestrant or do I try to filter first? Same quandary as noted above about trying to add enough chlorine to make the iron "angry" and precipitate out for filtering. Aggravate the iron for filtering and take a chance on subsequent stains? Various risk-reward angles.

If you add the sequestrant, you can try to filter, but don't be surprised if you don't capture much. If you do, let us know so we can capture the details of your process for others. As long as you don't use an excessive amount of chlorine at any point, the sequestrant should last for a reasonable amount of time as noted on the instructions. If you were to get algae and require a SLAM, I would expect that much chlorine would begin to breakdown and eliminate sequestrant faster.

 

[Katodude]

I did not stuff the filter with Polyfill in retrospect I should have.

I did stuff the skimmer with Polyfill which did nothing.

I also stuffed my robot with Polyfill and ran it a whole bunch which also did nothing.

My filter without Polyfill seem to capture a bunch of iron. This seem to work when I poured LC directly in the skimmer. I am hypothesizing that it precipitated in the pipes and got quickly captured by the filter. But then again, I could be completely wrong.

In the meantime my AA treatment worked great.

 

[Tiziano]

The AA articles are correct in recommending the use of a sequestrant quickly because they assume once the stains are lifted, the owner is going to start re-balancing right away. As such there is a potential for chlorine to aggravate the iron and we don't want the staining to reappear. But the articles can't address each pool owner's scenario. Once the iron is lifted off the pool surface, it MAY be available for filtration, but that depends on factors we cannot predict such as iron content and its propensity to be solid enough for filtration. It's a tricky deal - do I play it safe and bind the metals with sequestrant or do I try to filter first? Same quandary as noted above about trying to add enough chlorine to make the iron "angry" and precipitate out for filtering. Aggravate the iron for filtering and take a chance on subsequent stains? Various risk-reward angles.

Okay, that makes sense. I've jammed poly just about everywhere I can. Skimmer basket, pump basket and inside the filter. I need up not putting the cartridge in because I couldn't get the bolt rod to line up with poly fill in the center. I did put it all in a canvas bag so it doesn't get sucked into the piping.

I'll start to rebalance slowly via the skimmer basket with bleach. That's okay yea?

Any reason to not flip the SWG back on now?

And so I'm clear on it; sequestrant is really a product that just makes the iron soluble and keeps it from sticking to surfaces and staining? Which in turn makes it harder to filter because the particle size is so small? If that's the case, why is it part of the AA treatment vs just rebalancing the pool and calling it a day?

 

[Tiziano]

I did not stuff the filter with Polyfill in retrospect I should have.

I did stuff the skimmer with Polyfill which did nothing.

I also stuffed my robot with Polyfill and ran it a whole bunch which also did nothing.

My filter without Polyfill seem to capture a bunch of iron. This seem to work when I poured LC directly in the skimmer. I am hypothesizing that it precipitated in the pipes and got quickly captured by the filter. But then again, I could be completely wrong.

In the meantime my AA treatment worked great.

Okay. I couldn't get the cover on with the cartridge in it so stuffed a canvas bag with poly and put that in there and sealed it.

Did you use sequestrant at any point in your AA treatment?

 

[Texas Splash]

And so I'm clear on it; sequestrant is really a product that just makes the iron soluble and keeps it from sticking to surfaces and staining? Which in turn makes it harder to filter because the particle size is so small?

Correct. It binds to the iron and keeps it in a soluble state. It's used because as soon as you start introducing chlorine back to the water, there is a potential for the iron to react to the chlorine and try to stain again. The sequestrant helps to prevent that.

 

[Katodude]

i did use sequestrant but not right away. I am not sure when I used it.

 

[Tiziano]

Little update here. The iron staining is definitely much better and yesterday I began getting the FC back up but am now looking at cloudy water. I noticed it yesterday evening when I went to brush the pool. In addition to being cloudy there was also what looked like black/gray dirt on the surfaces. It had just rained very heavily, I don't know if that could have something to do with it.

This is a bummer because now I have to SLAM and understand that raising the FC to 24 is going to make the iron stain again.

The CuLator definitely has some yellow in it, so I'm happy I tried it. The polyfil I haven't seen work as well unless the grayish color in it is iron.

My question now is if using sequestrant while I SLAM will keep any of the iron suspended? If so, when in the process would I use it?

Or is using a bunch of algaecide instead of chlorine an option?

 

[Texas Splash]

If the cloudiness is indeed related to algae, the SLAM Process will remove the sequestrant sooner. But I would run an Overnight Chlorine Loss Test first before starting the SLAM just to be sure. Can't hurt.

 

[Tiziano]

If the cloudiness is indeed related to algae, the SLAM Process will remove the sequestrant sooner. But I would run an Overnight Chlorine Loss Test first before starting the SLAM just to be sure. Can't hurt.

Okay, thank you for the hopeful words! Haha, fingers crossed.