My Iron Stain Removal

[RPSalty]

@1200 pool is clear, no visible staining, clear sky today, 3/4" of rain yesterday. Poly-fill still in skimmers (no red).
FC: 2.5
CC: 0.0
pH: 7.6
TA: 100
CH: 475
CYA: 70
SALT: 3100
TEMPERATURE: 71°
CSI: -0.03
Added 1 cup acid

 

[RPSalty]

@1800
FC 4.0 CC <0.5
pH 7.8 just under
That's all I tested for the last day and a half, and those levels are mostly steady...pH rising slowly.
The water is clear. No red staining visible. There are a few spots that have a roundish dark ring around where I scraped off calcium growths in the past.

I took the poly-fill out today. It was starting to seriously restrict flow, pump strainer cap was sucking air. It was compacted and hard. Loosened up when removed. Sadly no red.

 

[setsailsoon]

@1800
FC 4.0 CC <0.5
pH 7.8 just under
That's all I tested for the last day and a half, and those levels are mostly steady...pH rising slowly.
The water is clear. No red staining visible. There are a few spots that have a roundish dark ring around where I scraped off calcium growths in the past.

I took the poly-fill out today. It was starting to seriously restrict flow, pump strainer cap was sucking air. It was compacted and hard. Loosened up when removed. Sadly no red.

l replaced the polyfil every few days... seemed to take a while 'till I got not no more rust specs.

 

[AndyTN]

So what I am gathering, by keeping the iron soluble, I can't filter it out. If I raise the FC and pH to the recommended levels, the iron will precipitate and become filterable but may/will also stain the pool surface.

Time is going to be key if you are going to use polyfil remove the iron. This is why I normally make it until July before I start seeing stains after my early spring AA treatment. You are not going to be able to keep your FC so low with your water temps and sunlight. Keeping a little polyfil in the water flow somewhere is going to allow the iron to slowly precipitate to it. You are getting the iron to precipitate to something you can easily throw away but it is not a silver bullet. Change out the polyfil a few times per month and it will also be unlikely to see a major change in color on the polyfil unless left in there for months.

The only sure way to eliminate the iron staining is to do a complete water exchange after AA treatment with water which has almost zero iron. I have a few places, like my fiberglass steps, which stain before the rest of the pool. If minor staining starts mid summer, I will put vitamin C tablets in a sock and rub it on the minor stains for spot treatment. This releases that iron back into the water to precipitate on something else, mostly on high flow areas like my skimmer or pump basket, which has polyfil in it.

 

[AndyTN]

Also, did you ever post a picture of your iron stains before AA treatment? I would be interested to see how bad it was to see how much of a challenge you will have mitigating future stains. Below is a pic of the worst my pool ever had the stains. This was my first season owning a pool and before I found TFP. The brown stuff at the water line is just leaves.

 

[RPSalty]

VIEWER DISCRETION
I apologize, I live in the country, no lanai, only pic I could find. Nevermind, I whited it out.

You can easily see the red on the main drain. Studying the rest you can see the red in patterns. I made the patterns adding MA through a pvc pipe directly to the surface. A good idea at the time but the staining was too extensive.

A little windy today, the water surface won't settle down. After treatment looks way better. My observation is the main drain was bright white following the AA treatment. It's looking like red is returning. I didn't put poly-fill in until a few days and it's out now.

I had stuffed both skimmers and turned off main drain. After a few days the pump was being starved for water. The poly-fill got dense and restricted flow. Can I put the poly-fill in a net and just have it in the skimmers?

 

[AndyTN]

Number one thing you want is flow through the polyfil. This is one of the reasons why your skimmer and main drain will be some of the first few places to show staining, because they get so much water flow. As long as you set it up so you are confident the water is flowing through the polyfil and not around it, give it a try.

 

[RPSalty]

@1800
FC: 3.5
CC: 0.5
pH: 7.6
TA: 100
CH: 450
CYA: 70
SALT: 3000
TEMPERATURE: 76°
CSI: 0.00

I'll figure out a way to get the poly-fill back in.

 

[kellyfair]

I live in Tampa - howdy neighbor!

I second the notion that the low FC just isn’t going to do the trick before too long. In fact, I freaked out a little when I saw your numbers, until I remembered it is only February!

 

[setsailsoon]

Is the photo on left right after AA and one on right now? Looks like a lot of iron came back. What sequestrant did you use? I used Metal Magic and it never looked like that. Still doesn't.

 

[AndyTN]

Is the photo on left right after AA and one on right now? Looks like a lot of iron came back.

I think he found an old picture to show the stains prior to AA.

 

[RPSalty]

Is the photo on left right after AA and one on right now?

The pic that has the critter whited out is before AA. The other is several days after. I used SC-1000 sequestant a few days after which may have been too soon.

This main drain is in the spa and is a return when not in spa mode. The red is returning.

Since the red is going to the plastic first, the covers come out, think removing and cleaning in MA would be a removal method? Then I could bundle short 1/2" pvc pieces and place in the skimmers, give the red what it wants.

 

[RPSalty]

I live in Tampa - howdy neighbor!

I second the notion that the low FC just isn’t going to do the trick before too long. In fact, I freaked out a little when I saw your numbers, until I remembered it is only February!

Howdy! Believe it or not I kept FC 3ish last year when the water temp was in the high 80's. My SWG is for 40k gallons and my pool is a liberal 18k. SWG @ 35-50 depending on sun hours and rain. I haven't seen algae, knock on plaster in almost a year.

Full disclaimer: I retired about then and was able to check FC and pH daily. Checking those two daily was key. Found I needed to add an average of about 1 cup of acid daily. Skip a day every once in a while. I was a PAP devotee previously and tests were only done weekly at best. Now that I follow TFP, I hope to bring the chemistry to recommended levels.

I would only dis PAP's testing results. I always followed their ABC's (not the shocking). Adding algaecide regularly is probably the real reason I didn't have algae at the low FC I kept last year.

 

[RPSalty]

@1300, clear water, clear sky, continues to show main drain getting darker.
FC: 3.5
CC: 0.0
pH: 7.8
TA: 90
CH: 400
CYA: 70
SALT: 3000
TEMPERATURE: 72°
CSI: 0.05
Added 1 cup acid

 

[kellyfair]

Took me way too long to figure out PAP. LOL

I kept CYA at 70, ran cell long enough to hit 6 or 7 for FC, and I think in 6 years I added acid twice.

That’s about it. Did SLAM when I found TFP, and again after a power blip tripped my pump timer and I didn’t notice For a few days. Other than that, my biggest issue was the ever-hated wasps. Speaking of them, I will be waging war early this year!

 

[setsailsoon]

The pic that has the critter whited out is before AA. The other is several days after. I used SC-1000 sequestant a few days after which may have been too soon.

This main drain is in the spa and is a return when not in spa mode. The red is returning.

Since the red is going to the plastic first, the covers come out, think removing and cleaning in MA would be a removal method? Then I could bundle short 1/2" pvc pieces and place in the skimmers, give the red what it wants.

Great idea, sacrificial PVC pipe! I love it. I'm actually going to try putting in a cationic resin bed in the flow. It serves the same purpose and I'm hopeful it will get out even the tiny amount that remains. Dilute MA or any remaining AA in solution should remove the iron very quickly.

Chris

 

[kellyfair]

Anyone else wanting to know what kind of critter?

 

[RPSalty]

Armadillo

 

[RPSalty]

Anyone else wanting to know what kind of critter?

Armadillo

 

[kellyfair]

Armadillo

Yikes!