Removing Iron

[joshua5438]

I am getting ready to start the AA process as I verified I have Iron staining in my pool. I am positive it came from my fill water as I am on a well. My questions..

1 - I have read that you should maintain with a sequester after completing the AA process. If I used Jacks Pink stuff, how would I know that I am maintaining the proper amount without waiting for the stains to come back?

2 - Has anyone found a floc that will actually bind the iron and allow it to be vacuumed out? CULater claims to remove metals but that doesnt make it true?? Would polyfill catch the iron after performing the AA treatment with sequestering treatment?

3 - Has anyone found a garden hose end filter for removing iron when topping the pool off?

Any other advice or tips would be great.

 

[JoyfulNoise]

I am getting ready to start the AA process as I verified I have Iron staining in my pool. I am positive it came from my fill water as I am on a well. My questions..

1 - I have read that you should maintain with a sequester after completing the AA process. If I used Jacks Pink stuff, how would I know that I am maintaining the proper amount without waiting for the stains to come back?

2 - Has anyone found a floc that will actually bind the iron and allow it to be vacuumed out? CULater claims to remove metals but that doesnt make it true?? Would polyfill catch the iron after performing the AA treatment with sequestering treatment?

3 - Has anyone found a garden hose end filter for removing iron when topping the pool off?

Any other advice or tips would be great.

1. You just dose according to the bottle instructions and follow the maintenance dosing. There are test kits that can measure some of the sequestering agent chemicals but they are expensive and unnecessary.

2. Unless you have a vacuum to waste option, floc is not advised. Even if you do have a vacuum to was option, not using floc properly can cause real problems. If you absolutely are intent on using a floc, I suggest you use one that is based on poly aluminum chloride (PAC) and you follow the directions to a tee. Problem is, you can floc sequestered iron so you have to let the pool water go brown and then try to floc. No guarantees it will work. Polyfill will not capture sequestered iron.

3. Most hose-end water filters are for removing chlorine/chloramines and heavy metals. Almost none of them remove iron because iron is not a contaminant. They also have a limited treatment capacity of a few hundred gallons at best. Mostly a waste of time and money.

 

[joshua5438]

1. You just dose according to the bottle instructions and follow the maintenance dosing. There are test kits that can measure some of the sequestering agent chemicals but they are expensive and unnecessary.

2. Unless you have a vacuum to waste option, floc is not advised. Even if you do have a vacuum to was option, not using floc properly can cause real problems. If you absolutely are intent on using a floc, I suggest you use one that is based on poly aluminum chloride (PAC) and you follow the directions to a tee. Problem is, you can floc sequestered iron so you have to let the pool water go brown and then try to floc. No guarantees it will work. Polyfill will not capture sequestered iron.

3. Most hose-end water filters are for removing chlorine/chloramines and heavy metals. Almost none of them remove iron because iron is not a contaminant. They also have a limited treatment capacity of a few hundred gallons at best. Mostly a waste of time and money.

So I really have no choice for removing iron? I assume this came from my well water as nothing else has changed. First time having this issue in 7 years of living here. Didn't have the issue after refilling after liner replacement 4 years ago. I did have the concrete replaced last year. Drained 50% of the pool, refilled and had no issues last year. Kept pool open for the first time over winter and now I have iron issues. It's all very odd to me.

As for letting the water go brown. How would I accomplish that? I assume I would do the AA treatment, let the water go brown and them floc and / or polyfill?

 

[jesse-99]

I am getting ready to start the AA process as I verified I have Iron staining in my pool. I am positive it came from my fill water as I am on a well. My questions..

1 - I have read that you should maintain with a sequester after completing the AA process. If I used Jacks Pink stuff, how would I know that I am maintaining the proper amount without waiting for the stains to come back?

2 - Has anyone found a floc that will actually bind the iron and allow it to be vacuumed out? CULater claims to remove metals but that doesnt make it true?? Would polyfill catch the iron after performing the AA treatment with sequestering treatment?

3 - Has anyone found a garden hose end filter for removing iron when topping the pool off?

Any other advice or tips would be great.

Jacks offers a test kit to check your ppm levels of the sequestrant I believe, otherwise you can just follow their recommended maintenance dosage (estimated obviously) which is shown on the bottle/instructions.

I've use Metal Trap (METALTRAP Filters (available in 3 sizes)) at the end of a hose... It seems to help a bit, but like anything that filters metals, the slower the GPM the better and the more metals it can capture.

You can also use the CuLator Fill Fast Pro (see here) Pool Water Pre-Filters Archives - CuLator Metal Eliminator and Stain Preventer for Pools and Spas which allows for swapable cartridge media and running it in parallel or series mode.

People have varying opinions on the CuLators (I recently bought (3) of the 4.0 versions for 3 of my 6 pumps), but the key is that they won't remove metals that have oxidized already, so you need to keep those metals sequestered so the Culators can work.

YMMV with any of these products obviously. Some people have better success than others. Keep your expectations reasonable.

 

[jesse-99]

So I really have no choice for removing iron? I assume this came from my well water as nothing else has changed. First time having this issue in 7 years of living here. Didn't have the issue after refilling after liner replacement 4 years ago. I did have the concrete replaced last year. Drained 50% of the pool, refilled and had no issues last year. Kept pool open for the first time over winter and now I have iron issues. It's all very odd to me.

As for letting the water go brown. How would I accomplish that? I assume I would do the AA treatment, let the water go brown and them floc and / or polyfill?

You basically have 2 options when it comes to iron.

#1 -- Use a sequestrant to keep the iron in solution and hold it there permanently (you have to keep up wiht the maintenance dosing!) . Then the iron won't turn your water green/brown or cause any staining if you have a plaster pool. It's a lot harder to remove from your pool in this state however (although CuLator may help for this so long as the iron hasn't oxidized, but peoples' opinion on the success of that product seem to vary greatly)

#2 -- Let your water turn green/brown, and in its suspended state, you CAN more easily filter it out, especially with using Polyfill in your skimmer basket(s). but this means, having ugly green/brown water for awhile (days or maybe a week or two) and risking staining your plaster which in turn might require a AA treatment or acid wash down the line.

It's a pick your poison scenario really... metals suck. Especially if your auto-fill water contains them, cause you're just introducing more metal back in over time.


EDIT --- your water will go from clear to green/brown because the chlorine oxidizes the iron in the water, which changes the water's color. the higher your FC, the quicker it goes green/brown. (again, IF not sequestrant is being used)

 

[Saturn94]

1. You just dose according to the bottle instructions and follow the maintenance dosing. There are test kits that can measure some of the sequestering agent chemicals but they are expensive and unnecessary.

This has been my experience using Jack’s Magic Purple Stuff for many years. At first I spent the money on the test kit, but I found the recommended dosage on the bottle kept it at the recommended level, so I stopped testing.

 

[Saturn94]

It's a pick your poison scenario really... metals suck.

Yes!

 

[AndyTN]

EDIT --- your water will go from clear to green/brown because the chlorine oxidizes the iron in the water, which changes the water's color. the higher your FC, the quicker it goes green/brown. (again, IF not sequestrant is being used)

Don't do this. It will just make all the iron precipitate and stain all the surfaces again.

 

[jesse-99]

Don't do this. It will just make all the iron precipitate and stain all the surfaces again.

It's that potential, but -not- necessarily. If you keep your pH low 7.0-7.4, it helps against staining, and it also depends on the ppm level of the metals in your water. However, that is truly the easiest way to get the iron OUT of the water. TONS of people on TFP let it go green/brown and then treat using Polyfill to get the iron out of the water, but it has to oxidize first. It sucks, but sometimes it's the -only- choice if it's already happened or you're in the middle of a SLAM, etc.

 

[joshua5438]

So, I already have staining on my stair, returns, skimmer, baskets, and vinyl liner. It's a solid yellow tint on everything. It easily wipes off with crushed vitamin C. I would prefer to remove the iron and not just "hide" it. Should I perform an AA treatment first to remove the staining or raise my FC to make it all oxidize? below are my current parameters. I use 12.5% liquid chlorine.

FC - 4
CC - 0
PH - 7.6
TA - 100
CH - 100
CYA - 30
Temp - 75F
Salt - 1700

 

[AndyTN]

Yes, that is some significant iron in your water. I get iron stains that gradually get more noticeable over time and do AA treatments a few times a year. What has worked the best for me is to immediately do a water exchange after AA treatment as I have pretty cheap water. I normally do this in July when the water has been evaporating for a few months and the new water is cooler for a couple weeks. My tap water in has iron in it so I have build a PVC pipe contraption which has Polyfil in it to filter out some of the iron from the tap. After pool has been refilled, I will hook it up to the pool pump with a hose and let it run for a few weeks to have some of the iron precipitate on the Polyfil. Summer is a bad time for treating iron stains because you can get away with low FC when the water is cold but low FC for more than a couple days in summer will lead to algae.

Here is my contraption which hooks up to the hose on one end and the fat part is 3" PVC which can hold a whole bag of Polyfil. The 2" pipe is pretty unnecessary as I just needed to have the attachments go from 1.25 inch up to 3". I then have a cap on the end which I have drilled many tiny holes for the water to spray out. Just put the pipe away from the pool before turning it off as you will get brown iron water leaking out without significant water pressure. The pressure from the pump compresses the Polyfil significantly compared to just putting Polyfil in your skimmer basket.

Anyway, you have to do something to start getting the iron out. I have yet to be able to eradicate the stains but just limit them.

 

[joshua5438]

AndyTN, correct me if I am wrong, but it sounds like you are not using a sequestrant after the AA and polyfil? You are doing an AA treatment to lift the stains and then running your water through the polyfil to remove as much iron as possible? I feel like this would be the best way to try and resolve my issue. I am also thinking of using some ALUM floc after the AA treatment to get some iron out. This is the first time having this issue in seven years so I am unsure what triggered the staining. Pool has been completely drained and refilled twice in that time period with no issues before.

 

[Texas Splash]

Remember, the AA treatment simply pulls the iron off of the pool's surfaces. It's still in the water. For that reason, those who can do a water exchange do so right away once the AA lifts the stains as it's the most effective way to ensure the iron is gone. For those on wells or location with high iron content in the new fill water, they try to do some pre-filtering as Andy does and/or periodically use a sequestrant in the new water as needed. But with evaporation comes the need for new water that potentially has more iron in it, so it's a vicious cycle.

 

[joshua5438]

Another question I have for all. Will the stairs being exposed to sun remove iron staining on it's own? I ask because my top step was stained like the others until my water evaporated enough to fully expose the top stair. Within a day, that top stair was stain free. I just wanted to confirm that iron reacts to sun exposure that quickly?

 

[Texas Splash]

Will the stairs being exposed to sun remove iron staining on it's own? I ask because my top step was stained like the others until my water evaporated enough to fully expose the top stair. Within a day, that top stair was stain free. I just wanted to confirm that iron reacts to sun exposure that quickly?

Interesting question that I don't recall encountering. Not sure if the iron was still present but changed its appearance due to lack of water, or some other potential reason. Lets call on @JoyfulNoise for some assistance on that question.

 

[joshua5438]

Remember, the AA treatment simply pulls the iron off of the pool's surfaces. It's still in the water. For that reason, those who can do a water exchange do so right away once the AA lifts the stains as it's the most effective way to ensure the iron is gone. For those on wells or location with high iron content in the new fill water, they try to do some pre-filtering as Andy does and/or periodically use a sequestrant in the new water as needed. But with evaporation comes the need for new water that potentially has more iron in it, so it's a vicious cycle.

That is what I have been a little confused on. The AA will release the iron from the surface but will it be able to bond to polyfil without adding FC to oxidize it? I want to attempt to remove as much as possible after the AA treatment. Would it be better to slam the pool to allow my water to turn from oxidation, perform the AA treatment and then filter and floc? Just trying to find the best process.

 

[Texas Splash]

Would it be better to slam the pool to allow my water to turn from oxidation, perform the AA treatment and then filter

That is certainly one option. The more angry you make the iron, the better chance you should have in mechanically filtering it out. I'm not excited about the floc though. I think if you do as you stated, perform the AA, then exchange water that should suffice.

 

[joshua5438]

That is certainly one option. The more angry you make the iron, the better chance you should have in mechanically filtering it out. I'm not excited about the floc though. I think if you do as you stated, perform the AA, then exchange water that should suffice.

I am not totally sold on the floc either. I have read of some really positive results from the ALUM floc with iron. I am still researching that one myself.

 

[AndyTN]

AndyTN, correct me if I am wrong, but it sounds like you are not using a sequestrant after the AA and polyfil? You are doing an AA treatment to lift the stains and then running your water through the polyfil to remove as much iron as possible? I feel like this would be the best way to try and resolve my issue. I am also thinking of using some ALUM floc after the AA treatment to get some iron out. This is the first time having this issue in seven years so I am unsure what triggered the staining. Pool has been completely drained and refilled twice in that time period with no issues before.

Yes, I forgot that piece but I don't use much, or sometimes I skip it, because the sequestrant keeps the iron from precipitating to the tiny fibers of the Polyfil. When your fill water has iron, it is just a process of removing incremental amounts each time you go through the AA process. The water exchange is just a shortcut to quickly reduce the iron content but it doesn't eliminate it. Using rain water to fill your pool would be iron free water but that is not scalable for 25k gallons.

If you do an AA treatment and have a special event coming up which you want the pool looking its best, definitely use the sequestrant to hide the iron temporarily. Other than that, it has to be removed at some point and $600 a year on sequestrant is not worth the $150 I spend on a water exchange.

 

[AndyTN]

That is what I have been a little confused on. The AA will release the iron from the surface but will it be able to bond to polyfil without adding FC to oxidize it? I want to attempt to remove as much as possible after the AA treatment. Would it be better to slam the pool to allow my water to turn from oxidation, perform the AA treatment and then filter and floc? Just trying to find the best process.

What I also do in my process when the water is still cold (not April-October) is I cap all the returns to the pool and hook up the PVC contraption for all the water from the pump to force its way through the Polyfil. I then take a gallon of bleach and poke a tiny hole in the bottom so it is able to drip bleach into my skimmer with the pump running. In combination with the ph at about 7.4, the little bit higher FC would help the iron precipitate to the inside of the pipes and to the Polyfil. That won't work with trichlor since it is acidic and won't work with a SWG because the flow is too slow, water too cold.

That brings be to another point. The inside of your plumbing and even your sand in your filter could have iron stains which you cannot see. I would do a 30-min backwash when the AA is still in the water and would try to keep the AA from moving through your plumbing back into the pool. See attached picture of the inside of one of my return pipes.