What I thought were old iron stains on my cartridge filters, is iron my water!

mguzzy

Gold Supporter
Hi all
Amazingly I found no posts on the forum about this. So I was the victim of the dreaded Iron contaminated Clorox Pool Salt about 3 seasons ago. Apparently it was worse than I thought. There is a nice darker area in my mottled dark plaster in the deep end from salt additions from that year. But I think the winter rain dilutions have gotten it mostly out of the pool But I am left with stained cartridge filters. I have done a TSP soak followed by an acid soak (per chemgeeks instructions). The stains are still there. I know its Iron because if I sprinkle some ascorbic acid on it they stains go away. Does the staining affect the filtration and I can just ignore it? or should I perform a ascorbic acid bath next?

Thanks all.
 
I think you can ignore iron stains on your filter. No iron is going to go back into your pool water.
 
Ok.. I was not particularly worried that the iron stains would go back into the water.. I more wondered if the stains affected the filtration of the cartridges. I have since given them a thorough cleaning with TSP, followed by acid washing and though they are whiter, the stains are still there in the form of brown spots. They are back in service and seem to doing well.
 
It can't hurt to give the cartridges an AA bath the next time you have them out for cleaning.
 
I've retitled this thread and perhaps the mods can move it to a more appropriate forum (@Leebo ) Probably one of the Water Chem forums...[Edit:thanks]

It appears I have a continuing iron problem.. Apparently the winter rains didn't get it out and it only got bound to something in the water. One never expects to deal with the iron thingy until it happens.

So since putting the filters back in service I also added a some MA to bring the TA down a bit while also doing the SWG/pH dance. Well, the next day the pool turned a nice emerald green. Its still TFP clear, just a nice shade of Creme de Menthe. Obviously the iron came out of solution and oxidized. Was it the addition of the MA, or residual chems from the TSP bath and acid wash? Whatever happened it coaxed the iron to show itself. Right now, I have a polyfill filter running in my skimmer basket that I made from the guts of 10,000 stuffed animals that were ripped up by the dogs. whoo hoo.

This mornings readings: pH 7.5 (stable for the last 4 days since the MA addition), Alk 110 (and stable), FC 5 (OTO), CYA 70ish, Water temp 73. The pool this morning was an enticing emerald green..a dash less than yesterday.
20200625_082226_sm.jpg
No, that's not the color of my plaster. If you notice the spa is less green, the valves are in spillover mode so it gets only the filtered water. The stuffed animal guts iron filter is working as it should! Before the morning rinse, the bucket has last nights rinse water
20200625_071820[1].jpg
I put a nylon sock on the basket over the top of the stuffed animal guts filter. Otherwise I get a billion leaves in the fibers and its a pain to pick them out. After the morning rinse, the bucket now has last nights and this mornings rinse water
20200625_072213[1].jpg
I'm hoping the iron will stay oxidized long enough for me to filter it out. I'm guessing if the pH changes it will become insoluble again and go back into solution.

My son didn't believe any of this hocus pocus. He just saw green and started screaming "DAD! there's algae in the pool!" Which of course started an argument as to why the pool was green. So after I showed him the way the polyfill filter worked and explained the iron chemistry thing, he sez.. "Why didn't they teach us something cool like this in high school chemistry!"
 
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My town has high iron in the water supply. When we had our liner replaced and refilled the pool. You couldn’t even see the drain in the deep end because the water was so clouded by the iron.

I took a cheap pillow that has that Polly filling and pulled it out of the pillow and stuffed it in both skimmers.

I turned off the main drain and let the pump run all night. In the morning , both skimmers were dark orange with the collected iron. It took awhile but if finally cleared up. That pillow trick worked good.
 
Update. I filtered all day yesterday and through the night. I rinsed the polyfill this morning and it was noticeably cleaner. So was the pool. By afternoon it is catching much less iron and the pool is back to looking TFP clear. So either I have filtered about all I'm going to get or the iron has snuck back into solution. I'm going to leave the stuffed animal guts in the filter through the weekend to see if it filters anything else, and I'm going to put the filter back on its regular schedule. I didn't know if this process was going to take a week or what.. so it really only took a few days.
 
I am resurrecting this thread.. Wake UP!

After consulting the wiki and all the other resources of this fine place I am getting ramped up to do a AA and MM treatment following @setsailsoon 's basic recipe from:

I had planned on doing this as a part of my "soft" opening this year. woop woop. So far this off season, I have collected an 8lb bucket of AA, found it on sale, 2 quarts of MM, also on sale, of course some jugs of MA and Cl are ready and waiting. And thanks to my dogs I have all the polyfil I need in the form of the guts of 10000 eviscerated beanie babies. My water is still pretty cold (52 F this morning) so I don't think I will have a lot of bio activity, and I plan on bring the pool up to 60 when I do the MM per their instructions. And thanks for all the preparatory feed back from @setsailsoon, @markayash, and as always @JoyfulNoise , (he's ma hero!)

Stay Tuned Test GIF by xponentialdesign

...stay tuned...
 

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I am resurrecting this thread.. Wake UP!

After consulting the wiki and all the other resources of this fine place I am getting ramped up to do a AA and MM treatment following @setsailsoon 's basic recipe from:

I had planned on doing this as a part of my "soft" opening this year. woop woop. So far this off season, I have collected an 8lb bucket of AA, found it on sale, 2 quarts of MM, also on sale, of course some jugs of MA and Cl are ready and waiting. And thanks to my dogs I have all the polyfil I need in the form of the guts of 10000 eviscerated beanie babies. My water is still pretty cold (52 F this morning) so I don't think I will have a lot of bio activity, and I plan on bring the pool up to 60 when I do the MM per their instructions. And thanks for all the preparatory feed back from @setsailsoon, @markayash, and as always @JoyfulNoise , (he's ma hero!)

Stay Tuned Test GIF by xponentialdesign

...stay tuned...

Any leftover AA can be used for bread making. AA is a natural preservative that will lengthen the shelf life of homemade breads. It is also a nutrient the yeast can use to improve the leavening process.

If you can find a cal hypo puck (not easy to find unfortunately), you can add one to the poly fill inside the skimmer to help force iron precipitation there once you begin to re-chlorinate the water. The high pH and concentrated chlorine inside the skimmer’s small volume will help iron to come out of solution. It’s not required but it’s a nice little trick to do if you can pull it off.

Good luck to you.
 
Ok.. I spent Saturday hunting and gathering.
Borax, two random boxes from the laundry room-check ✔️
💪&:hammer: from the pantry-check✔️
Chlorine, 4gal-check ✔️
Salt-check ✔️
Tequila -hic🍸
Metal Magic-check ✔️
Vitamin C-8lbs-check ✔️
Fresh gal jug of MA-check ✔️
The polyfil guts of 10,000 eviscerated beanie babies-check ✔️

I also charged up all my technology so I could record the event in case something happened
2 GoPros, one camcorder, one Note8-check ✔️
 
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Sunday.. big day.. first I needed to find some appropriate music for the event.. I need some pool music.. ahh.. got it:
Kurt Cobain Baby GIF by jbetcom

Ya know how I know its tax season? Because I start working on every other chore that has been sitting around for a year instead of my taxes... I have fixed 3 small appliances in the last two days, a broken window slider on my car and today I'm going to watch my pool un-brown.. yeah yeah yeah,...

Now where'z zat dang Tequila.. Its a holiday!
 
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  • Haha
Reactions: Ignoramus
Ok.. I spent Saturday hunting and gathering.
Borax, two random boxes from the laundry room-check ✔️
💪&:hammer: from the pantry✔️
Chlorine, 4gal-check ✔️
Salt-check ✔️
Tequila -hic🍸
Metal Magic-check ✔️
Vitamin C-8lbs-check ✔️
Fresh gal jug of MA-check ✔️

I also charged up all my technology so I could record the event in case something happened
2 GoPros, one camcorder, one Note8-check ✔️
“ honey what are you doing, need to cut the grass” “ can’t watching the Vitamin C lift stains”
 
Ya know how I know its tax season? Because I start working on every other chore that has been sitting around for a year instead of my taxes...

Seriously!! I am totally tackling the grout stains in my shower tomorrow as opposed to doing my taxes .... I might even get some Costco shopping in first.
 
Day1
1) First I cleaned my filters out real good. I know the AA wikie says to take them out, but I have an old set of filters that I use for just these occasions, and I'll swap out the good ones after all this is done
2) I did a full panel of tests:
Filter press 13 psi
Water temp 54F.. At this temp I am hoping that the bio activity is suppressed enough that I don't have to use PolyQuat
Salt 3200.. hmm I screwed this up.. I did the test on 25 ml instead of 10..what was I thinking.. I wasn't. So I divided the result by 2.5, I'll do it again later.
pH 8.2
OTO Cl 0.5
Alk 80
CYA 70
CH 275ish
2) Per Pool Math I added ~.5 gal of MA to drop my pH to 7.2.. let things mix for a bit while I fussed with other things. And confirmed the pH.. dang that app is good...nailed it!
3) Turned off the SWG a few days ago.. confirmed it was still off
4) Stuffed the skimmer basket with polyfill balls
5) Lights, Camera's are stationed, 2 GoPros underwater, camcorder above. action.....
6) Added AA at a rate of .5 lbs/10K in .5 lb increments. I sprinkled in about a pound and the another pound and watched... and watched....and watched...

20210404_125930[1].jpg

Dad? Is something supposed to happen?
 
Day 2
Welp the pool is still there. It didn't explode or turn into a black hole. The whole idea was to do the AA/Iron treatment as a part of my yearly soft open.. and use the cooler water temps to keep my algae in check.. so far it seems to be working. And flush all the gunk that will be created with the treatments using my off season filters. We shall see.

The algae seems to be in check. I checked the pH and its down to 6.8! Alk still 80... So I need to bring that up with Borax. Also the pool needs to be over 60 deg and pH of 7.5 per the MM directions so I started the heater this morning and got it to 65 whilst I was doing the 20 Mule Team-pH waltz. According to AA wiki it wants me to keep pH at 7.2... but I'm going up another .3 to accommodate the MM directions.

11-ish.. last AA addition.. I think I stopped at about 3.5 pound total.
Noon-ish dumped in what was left of the first box of Borax.. I'm guessing that was about 50 oz that got me to pH of 7.2.. Alk holding steady at 80
2-ish.. added another 34 oz per pool math.. then I noticed the pool volume got reset so I recalculated.. that makes more sense...
4-ish- pH 7.3ish, not a lot of change. I turned on the waterfall for some more aeration.. so nice to have the pitter-patter of falling water, so feng shui.
5-ish looks like the aeration is helping.. I am up to 7.4 ish.. I added another 16 oz per Pool math.
7-ish got it to pH 7.5 for sure.. so I dumped in the two 32 oz bottles of MM and I will revisit it in the morning.

The pool is clear, but It looks to have a tad Creme de Menthe green hue.. not as much as when this happened last season. There is no discoloration in the polyfil in my skimmer. But the pool sweep hose is nice and white! Lets see if the Metal Magic shakes anything loose.
20210405_121441[1].jpg20210405_181108[1].jpg

My kids said.. "Dad! what's with all the videos? Are you going to be a Pool Tuber?" ..kids! I checked my film footage.. I had one GoPro pointed at the bottom from the step out in the deep end and the other was mounted on the pool sweep. Well that was a cinematic bust. Alas I really couldn't see that much change on my dark plaster. The GoPro on the sweep could just as well been wandering around on the moon.. except, I'm pretty sure the moon doesn't have waterline tile last time I checked. I think I will go back to using my GoPro to make sure the light goes out inside the refrigerator.

I did do some before and after shots and short vids of some of the internals of my pool gizmo's
Pool sweep backup valve inerds, before and after:
20210404_141040[1].jpg20210405_212132[1].jpg

Skimmer diverter float valve before and after:
Screenshot_20210405-211206_Video_Editor[1].jpg20210405_211409[1].jpg

Those before and after shots took about 90 secs and were using a much higher concentration of AA than what I dumped in the pool. I think I would have to dump 100 lbs in the pool to get an AA concentration for an immediate change like that. The staining is more prevalent where the water is moving faster. Like here at the skimmer entrance:
20210404_140727[1].jpg
Enough cut and pasting for today.. Tomorrow I see if the MM will make any difference.
 
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