Iron Stains Return And Return And Return

[Westy]

I've read all the posts on several pool maintenance forums regarding iron stain removal. I have used the Stain Free (ascorbic acid) and Metal Free (sequestrant) now three separate times. Each time, I have performed the stain removal at pH of 7.0 with FC at zero. I've cleaned cartridge filter after each treatment and then brought FC up slowly at a rate of about 1 ppm per day. As soon as my FC reaches the low end of the "best guess" level, the stains return. It seems to me that either the sequestrant is not working, or it is binding with the free Fe in such small particles that it continues to circulate through my filter. As soon as I bring pH and FC up, even slowly, the iron is again deposited onto the pool walls. With the last treatment, I kept the pH at 7.2 as I raised the FC, still had stains return as soon as FC reached 3 ppm (after about 4 days). The expense involved with this unsuccessful treatment is beginning to outweigh the minimial benefit (1 or 2 days with clean pool walls)! Pool fill water comes from an automatic float/filler which is direct from our well, hence we are always adding new iron to the pool.

Am I stuck with orange walls?

[waterbear]

I have found the MetalFree (EDTA) to be not as effective as HEDP based sequesterants like Proteam Metal Magic or Jack's Magic Pink Stuff at keeping the staining away. Use a double dose of the sequesterant initially and be sure to add a maintenance dose (or in your case more since you are always adding water with iron in it) on a weekly basis and keep your pH at the low end of the scale (about 7.2). Is your pool fiberglass or plaster? Often, if the stains start to come back you can just drop your pH to about 7.0 and add another dose of seqeusterant and they will go away if you catch them just as they start. I ususally only have to do the acrobic acid once a year and then by keeping sequestant in the wate I am able to keep my white fiberglass pool stain free. The staining will usually start to deposit if you let your pH climb too high and if you have a high santizer level. Also, when you raise your FC after the ascorbic acid use liquid chlorine or bleach and pour it into your skimmer. This way you might deposit iron on the filter instead of in your pool. You will have to acid wash the cartridge to remove the iron. To do so first soak the cart overnight in a solution of 1 cup of automatic laundry detergent to each 5 gallons of water to remove organics (or they will harden into a cement like mess and ruin the cart), hose it off well, then soak it in a solution of one part muriatic acid to about 20 parts water for about 30 minutes or so. Hose it off again.

Stain removeal is not a one shot deal but something you have to keep on top of if your water contains metals. As an alternative you might want to consider a water softener and use the softened water to fill. The ion exchange resin is effective at removing iron from the water. If your iron is very high you might want to consider a 'green sand' or other special iron removing ion exchange resin for your fill water.

[Westy]

waterbear, thanks for the reply...I have read many of your previous posts. In answer to a couple of your questions, my pool is fiberglass. I lowered the pH this morning to about 7 and got in the pool and scrubbed around the waterline where the staining was worse with a sock full of vita C tablets, it came right off. I added more metal free (I'll try the other sequestrants you suggested) and still have the pH at 7 with FC near zero. I'm not sure completely what my next step will be, maybe I'll bring FC up by additions of bleach into the skimmer and do the acid wash. On the other hand, I've got new filters coming soon so I think what I'll do is wait for the new filters and do the treatment again but instead of doing the acid wash, I'll just discard the old filters as I was going to do so anyway. I did a drain/refill this winter to deal with previous owner's negligence regarding CYA and the refill was totally with SOFT water! All the iron in the pool now has probably come in solely from the auto filler bringing in well water. I may have to look at replumbing the fill water system or filtering it.

[psujerry]

I've read all the posts on several pool maintenance forums regarding iron stain removal. I have used the Stain Free (ascorbic acid) and Metal Free (sequestrant) now three separate times. Each time, I have performed the stain removal at pH of 7.0 with FC at zero. I've cleaned cartridge filter after each treatment and then brought FC up slowly at a rate of about 1 ppm per day. As soon as my FC reaches the low end of the "best guess" level, the stains return. It seems to me that either the sequestrant is not working, or it is binding with the free Fe in such small particles that it continues to circulate through my filter. As soon as I bring pH and FC up, even slowly, the iron is again deposited onto the pool walls. With the last treatment, I kept the pH at 7.2 as I raised the FC, still had stains return as soon as FC reached 3 ppm (after about 4 days). The expense involved with this unsuccessful treatment is beginning to outweigh the minimial benefit (1 or 2 days with clean pool walls)! Pool fill water comes from an automatic float/filler which is direct from our well, hence we are always adding new iron to the pool.

Am I stuck with orange walls?

[psujerry]

I've read all the posts on several pool maintenance forums regarding iron stain removal. I have used the Stain Free (ascorbic acid) and Metal Free (sequestrant) now three separate times. Each time, I have performed the stain removal at pH of 7.0 with FC at zero. I've cleaned cartridge filter after each treatment and then brought FC up slowly at a rate of about 1 ppm per day. As soon as my FC reaches the low end of the "best guess" level, the stains return. It seems to me that either the sequestrant is not working, or it is binding with the free Fe in such small particles that it continues to circulate through my filter. As soon as I bring pH and FC up, even slowly, the iron is again deposited onto the pool walls. With the last treatment, I kept the pH at 7.2 as I raised the FC, still had stains return as soon as FC reached 3 ppm (after about 4 days). The expense involved with this unsuccessful treatment is beginning to outweigh the minimial benefit (1 or 2 days with clean pool walls)! Pool fill water comes from an automatic float/filler which is direct from our well, hence we are always adding new iron to the pool.

Am I stuck with orange walls?

[psujerry]

I've read all the posts on several pool maintenance forums regarding iron stain removal. I have used the Stain Free (ascorbic acid) and Metal Free (sequestrant) now three separate times. Each time, I have performed the stain removal at pH of 7.0 with FC at zero. I've cleaned cartridge filter after each treatment and then brought FC up slowly at a rate of about 1 ppm per day. As soon as my FC reaches the low end of the "best guess" level, the stains return. It seems to me that either the sequestrant is not working, or it is binding with the free Fe in such small particles that it continues to circulate through my filter. As soon as I bring pH and FC up, even slowly, the iron is again deposited onto the pool walls. With the last treatment, I kept the pH at 7.2 as I raised the FC, still had stains return as soon as FC reached 3 ppm (after about 4 days). The expense involved with this unsuccessful treatment is beginning to outweigh the minimial benefit (1 or 2 days with clean pool walls)! Pool fill water comes from an automatic float/filler which is direct from our well, hence we are always adding new iron to the pool.

Am I stuck with orange walls?

I read your posts. I think the problem you are having is that you must get rid of the iron after you used the metal sequestering agents. The iron is still in your pool water, and as soon as the pH rises with sufficient chlorine levels are reached to oxidize it, the stains reappear . There are only 3 ways to prevent this that I know of. Either use lots of sequestering agents often, or drain the pool water completely to get rid of the iron, or filter the iron out. You cannot completely filter the iron out using standard cartridge, sand or DE filters, as the particle size if the iron can still go through these filters. I am aware of a reasonably priced filter contraption called Metaltrap, that actually filters out all the iron by recirculating the water back into the pool after you remove the stains off the pool surface. I think the name of the company is called WaterTight Systems in Jacksonville, FL.

[Westy]

I read your posts. I think the problem you are having is that you must get rid of the iron after you used the metal sequestering agents. The iron is still in your pool water, and as soon as the pH rises with sufficient chlorine levels are reached to oxidize it, the stains reappear . There are only 3 ways to prevent this that I know of. Either use lots of sequestering agents often, or drain the pool water completely to get rid of the iron, or filter the iron out. You cannot completely filter the iron out using standard cartridge, sand or DE filters, as the particle size if the iron can still go through these filters. I am aware of a reasonably priced filter contraption called Metaltrap, that actually filters out all the iron by recirculating the water back into the pool after you remove the stains off the pool surface. I think the name of the company is called WaterTight Systems in Jacksonville, FL.

psujerry, certainly that is part of the problem, I'm never really removing the iron from the water. Using waterbear's strategy, I do believe I've been able to "stain" the filter to some extent, I'm also really watching pH to keep iron of the pool walls. I'm going to check out the "Metaltrap"

[CrazyPoolMom]

I am pretty sure that I was able to remove all of the initial iron debris fallout from the first round with just my intex pump and paper filter. I was unable to leave for the weekend to get the necessary chemicals, so I just kept the ph lowered, cut the chlorine, and kept filtering and vacuuming. Everytime I washed out the filter, several times a day, (and night) it was covered with rust colored stuff. I used the Hayward aqua critter and vacuumed directly into the filter, and that water was very clear, and very clean.

Unfortunately I did not get the metal sequesterant in before raising the chlorine level, and the PH went up also, so I have more iron fallout, and am now in the process of following waterbears directions:)