Metal Magic

[jonathan8610]

I believe I have some type of metal in my pool water, just not sure if it is iron or copper. I am on well water. After completing a SLAM process a few weeks ago, I noticed my water was clear but bright green so I let the chlorine levels drift down and did an initial dosage of Metal Magic and the water turned clear blue but cloudy. After 48 hours, I brought my chlorine level up from 2ppm to 6ppm and unfortunately, that seems to have precipitated the metals out of the solution as the water is now teal green. So now I am trying to come up with a weekly process for managing how to tackle this problem best. Based on my CYA of 40 my recommended target FC level is 5-7 but I may need to keep it closer to 3 for a while to prevent oxidation of the metals, but I also do not want to risk algae developing and the need to shock the pool.

I figure I will need to add a weekly maintenance dose of Metal Magic to the water to keep the metals sequestered but really struggling to figure out how to maintain my FC levels to avoid algae outbreaks. I was considering maybe supplementing with Poly60 but unsure how that interacts with Metal Magic and when to use each product, and if the application of that product even makes sense.

 

[Texas Splash]

Next time the iron (that's what I would assume being on a well) starts to precipitate out, I would head for the polyfill and place some in the skimmer. Also consider an additional filtration method to help capture as much iron as you can via polyfill. It can only be done while it's in its precipitation for however, and Metal Magic being a sequestrant will keep you from mechanically grabbing as much as you would like. Once you have exhausted all of the poly/mechanical filtering, then carefully adjust FC and watch for subtle changes in the water. Then you may have to rely on a good sequestrant. Poly-60 is fine as long as the FC level doesn't go too high. Of course if the pool ever gets algae and requires a SLAM Process, all bets are off. The FC will most certainly aggravate the iron, so that's an ideal time to do the polyfill filtration.

 

[Texas Splash]

 

[jonathan8610]

When the metal was oxidized in the water I added PolyFil to the skimmer and was unable to catch anything besides debris. Is the method outlined above more effective than stuffing the skimmer with it? I spoke to someone at Pro Team who mentioned that liquid chlorine is high in pH which may have caused the discoloration after the initial dose, but I do not want to add a different form of chlorine, so maybe I just need to add smaller more frequent doses?

 

[Texas Splash]

Whether you place polyfill in the skimmer or in a separate container to run water through, it's the same concept - mechanical filtration. But it only works when the iron is in a particular state large enough to be filtered. If the water is relatively clear or there is a sequestrant in the water, it probably won't work. Whenever your FC level rises, there is a chance of iron precipitation (water color changes, pool staining). The FC level to when that happens can vary based on the iron content, CYA, pH, and FC level among perhaps other factors. But in its simplest form, the more you can filter out the easier water management will be for you later. Free chlorine is free chlorine, so whether you use powdered, granules, or liquid chlorine, it can still aggravate the iron if it gets high enough. An elevated FC and pH coupled with a high iron content = reaction. Try to keep the pH relatively low, and do a balancing act with your FC on the low end if you need to and monitor. Just don't let the FC get so low you end up with algae. A Poly-60 dose may be beneficial at times.

 

[ajw22]

When the metal was oxidized in the water I added PolyFil to the skimmer and was unable to catch anything besides debris. Is the method outlined above more effective than stuffing the skimmer with it?

Either polyfill method will work equally well.

Put an iron filter on your fill water source from your pool as described in Iron Fill Water Filter - Further Reading. The filter will not help with the iron int he pool but can help lessen future problems once you get this cleared up.

I spoke to someone at Pro Team who mentioned that liquid chlorine is high in pH which may have caused the discoloration after the initial dose, but I do not want to add a different form of chlorine, so maybe I just need to add smaller more frequent doses?

Lets set the record straight. From PH - Further Reading

It is a myth that liquid chlorine will raise pH. The myth is based on a misunderstanding of chlorine chemistry.

Adding liquid chlorine to water can cause a temporary increase in pH which is usually offset by the chlorine reacting with organics and biological matter which are acidic (creates a proton) reactions. Thus, on balance, the net chlorine reactions are pH neutral.

Most retail and commercial liquid chlorine products contain a small excess of lye from the manufacturing process but this amount of OH- is minimal and does not change the pH with normal levels of liquid chlorine use.

If one were to add significant amounts of liquid chlorine (for example, raising the pool water chlorine concentration to SLAM FC levels), then the pH rise would need to be offset by an initial lower of the pH with acid. This is why TFP requires a pool owner to adjust their pH down to 7.2 prior to starting the SLAM Process.

Adding liquid chlorine DOES increase the pH at first, however as it's used up the acid that's created lowers it back down to where it was before......thus equaling each other out making it pH neutral.

It is that initial pH rise that turns the pool green and if you wait a day or two the pH will drop and the pool will turn blue again.

 

[jonathan8610]

Either polyfill method will work equally well.

Put an iron filter on your fill water source from your pool as described in Iron Fill Water Filter - Further Reading. The filter will not help with the iron int he pool but can help lessen future problems once you get this cleared up.



Lets set the record straight. From PH - Further Reading

It is a myth that liquid chlorine will raise pH. The myth is based on a misunderstanding of chlorine chemistry.

Adding liquid chlorine to water can cause a temporary increase in pH which is usually offset by the chlorine reacting with organics and biological matter which are acidic (creates a proton) reactions. Thus, on balance, the net chlorine reactions are pH neutral.

Most retail and commercial liquid chlorine products contain a small excess of lye from the manufacturing process but this amount of OH- is minimal and does not change the pH with normal levels of liquid chlorine use.

If one were to add significant amounts of liquid chlorine (for example, raising the pool water chlorine concentration to SLAM FC levels), then the pH rise would need to be offset by an initial lower of the pH with acid. This is why TFP requires a pool owner to adjust their pH down to 7.2 prior to starting the SLAM Process.

Adding liquid chlorine DOES increase the pH at first, however as it's used up the acid that's created lowers it back down to where it was before......thus equaling each other out making it pH neutral.

It is that initial pH rise that turns the pool green and if you wait a day or two the pH will drop and the pool will turn blue again.

Thank you, that makes sense. I will look into that option for next year when I refill the pool. I typically don't need to add water from my hose during the season and just rely on rainfall to replenish what is lost due to backwash/etc. Thanks for that background information regarding chlorine/pH.

 

[jonathan8610]

Whether you place polyfill in the skimmer or in a separate container to run water through, it's the same concept - mechanical filtration. But it only works when the iron is in a particular state large enough to be filtered. If the water is relatively clear or there is a sequestrant in the water, it probably won't work. Whenever your FC level rises, there is a chance of iron precipitation (water color changes, pool staining). The FC level to when that happens can vary based on the iron content, CYA, pH, and FC level among perhaps other factors. But in its simplest form, the more you can filter out the easier water management will be for you later. Free chlorine is free chlorine, so whether you use powdered, granules, or liquid chlorine, it can still aggravate the iron if it gets high enough. An elevated FC and pH coupled with a high iron content = reaction. Try to keep the pH relatively low, and do a balancing act with your FC on the low end if you need to and monitor. Just don't let the FC get so low you end up with algae. A Poly-60 dose may be beneficial at times.

Thank you for the response, I will add PolyFil back to the skimmer to see if it's successful in helping filter anything additional out. The rep from Pro Team said he is going to send me a product to use that is in development that I think is similar to PolyFil or the CuLator that he said you put in your skimmer basket and it helps to catch the metal as well. I am supposed to take a water sample before and after use and send it back to their lab to see if it was successful at removing any metals, so I'll be sure to update this post with the results there.

In terms of the weekly process, my plan was to add a weekly amount of Metal Magic & PolyQuat 60 but wondering if there is a best practice for applying both of those chemicals (meaning different days or different times), so there is no issue (not sure if there is anything that would be counterproductive).

 

[Texas Splash]

In terms of the weekly process, my plan was to add a weekly amount of Metal Magic & PolyQuat 60 but wondering if there is a best practice for applying both of those chemicals (meaning different days or different times), so there is no issue (not sure if there is anything that would be counterproductive).

Timing wise between the two, not that I am aware of. My only recommendation is that if you plan to try the polyfill or other mechanical filtering product in the skimmer, do that before adding any sequestrant. Metal Magic will keep the iron in suspension and you'll never catch any of it. I think the Poly-60 is a good algae preventative consideration this time of year if your FC should be on the low end.