Iron out or Metal Out?

[shadylady23]

Hey guys. So I tried to search and didn’t find any answers. I used this Metal Out last year not knowingly and it DID seem to help my water get clear from the browing caused by chlorinating. But now that I’ve been reading on TFP, I wanted to check with the pros that it’s actually okay to add to help get the iron or whatever Metal I have going on? Added water upon opening this year so I’ve got some browning again. Neither bottle says what’s in it?!

1: Do you guys know if either one of these are okay? (The directions appear to be the same)

2: The directions say to let FC down to ZERO?! Prior to adding? I definitely didn’t do that last year. Is that really necessary? I’d be afraid algae would get going again

- - - Updated - - -

I don’t notice any staining on my liner or anything though, which everyone talks about. My skimmer does have a line now though.

 

[JoyfulNoise]

These are likely a mixture of ascorbic acid, citric acid and oxalic acid. The ascorbic and citric acids will dissolve iron stains while the oxalic acid can combine with dissolved iron to form an insoluble iron compound. Problem is, oxalic acid reacts with calcium in the same way and, because your calcium hardness is a lot higher than the iron concentration, it will probably remove more calcium than iron. All of those chemicals are destroyed by chlorine which is why FC levels have to be zero. If there is any dissolved iron in water when the chlorine is restored, it will oxidize back to brown color again. The only solution for iron contaminated water is to use a longer lasting sequestrant based on HEDP (fir example, Jack’s Magic product line or ProTeam Metal Magic). However, all sequestrant require constant maintenance doses and you typically need to keep your pH and FC on the low side to avoid oxidation of the sequestrant.

You can try to filter out as much of the solid iron as you can using the polyfill but you won’t get all of it and anytime you refill you’ll be adding iron back in.

 

[shadylady23]

Thanks! Trying to comprehend that!

 

[funandsun]

Shadylady JoyfulNoise is an expert, so you are going to have to speak up if what I say and what he says seems to contradict.

I put Vitamin C tablets on my stairs and my liner as you can see here in the pictures. The stain lifted instantly.


I used Metal Out. I did it 5 days post SLAM/OCLT. I let the FC drop to zero, my pH was already 7.2, I put my sand filter on recirculate and added 1 quart and let that go for 24hrs. (I followed the directions)

Before (see the shallow end)


After (turns out the whole pool was covered, we had no idea how bad it was)


Seriously.... after 24hrs... 12hrs it didn't look this promising, it was improved but 24hrs and this was it. I say that to reinforce the idea that Pool Owner Patience is required.

I immediately raised my FC to 3ppm (my CYA was 30) and 2 hours later I raised it to 5ppm FC and I maintained 5-8ppm the rest of the season.

Now, in all fairness, by mid Sept, I could have added 1/4-1/2 of a bottle because by then (that after pic was july 4th 2017), I could see the sequestrant was breaking down, but our swimming season was over and I didn't want a partial bottle open all winter.

I will be doing the same thing this year again.

Hope that helps you out.

 

[JoyfulNoise]

funandsun,

Those are great pictures and they show how effective ascorbic acid can be at dissolving iron stains. And so it sounds like you have found an effective treatment for your pool.

The overall point I was trying to make was this - these products do not, in general, remove iron from your water. They can lift iron stains from the surfaces of your pool and dissolve the iron back into your pool water, but they do not get rid it. Sometimes iron can be oxidized by chlorine to form a fine suspension of iron oxide particles that can then be filtered out, but it’s more often the case that the iron oxide settles and adheres to surfaces rather than staying suspended in the water. Sequestrants are the only way to keep iron dissolved in water and, if the sequestrant is maintained properly through regular dosing, you won’t see the iron at all. What result one gets is very much dependent on the concentration of iron in the water and how much iron-laden water one adds throughout the season. If concentrations are low and rain water is plentiful (or fil water with no iron in it), then a single treatment fix is possible. If concentrations are higher, then regular dosing is likely going to be necessary.

 

[funandsun]

funandsun,

Those are great pictures and they show how effective ascorbic acid can be at dissolving iron stains. And so it sounds like you have found an effective treatment for your pool.

The overall point I was trying to make was this - these products do not, in general, remove iron from your water. They can lift iron stains from the surfaces of your pool and dissolve the iron back into your pool water, but they do not get rid it. Sometimes iron can be oxidized by chlorine to form a fine suspension of iron oxide particles that can then be filtered out, but it’s more often the case that the iron oxide settles and adheres to surfaces rather than staying suspended in the water. Sequestrants are the only way to keep iron dissolved in water and, if the sequestrant is maintained properly through regular dosing, you won’t see the iron at all. What result one gets is very much dependent on the concentration of iron in the water and how much iron-laden water one adds throughout the season. If concentrations are low and rain water is plentiful (or fil water with no iron in it), then a single treatment fix is possible. If concentrations are higher, then regular dosing is likely going to be necessary.

Yes, I totally followed and I hope shadylady understands that too, Metal Out is NOT going to REMOVE the iron from the water. Whatever iron I had in my water last year is still there this year (other than any that has been removed during splash out or backwash).

Cheers,