Doing an AA treatment

[Katodude]

And our cold snap is over....

Temp 69
FC 3
ph 7.4

I have been adding chlorine very slowly to the skimmers with the polyfill in an effort to try to precipitate some of the iron out. The Polyfill remains clean. Running the polyfill robot again to see if it can pick something up.

Should I drop the pH again, or at this point declare victory and let the pool slowly come up to normal?

I have the purple stuff also that I have not added. Maybe just do that first and continue to let the pool drift up. I have held off adding the sequestrant in an effort to try to capture some of the iron.

 

[red-beard]

Didn't I read in one of these threads to put a calhypo tablet on top of the polyfill?

 

[mknauss]

Very hard to find a cal hypo tablet.

I wonder if one used a very fine mesh sock or bag and put cal hypo granules in it and set it on the polyfill? Pretty cheap to test it.

 

[JoyfulNoise]

And our cold snap is over....

Temp 69
FC 3
ph 7.4

I have been adding chlorine very slowly to the skimmers with the polyfill in an effort to try to precipitate some of the iron out. The Polyfill remains clean. Running the polyfill robot again to see if it can pick something up.

Should I drop the pH again, or at this point declare victory and let the pool slowly come up to normal?

I have the purple stuff also that I have not added. Maybe just do that first and continue to let the pool drift up. I have held off adding the sequestrant in an effort to try to capture some of the iron.

You need to use the sequestrant or else the iron staining is going to come back.

 

[Charlie Bezzina]

Would it be better to raise the fc to slam levels immediately, in order to force the iron to oxidised fast in the water rather than slowly on the plaster? You can then do your filtering.

 

[JoyfulNoise]

You can’t control where the iron will precipitate. If you shock the water you will most likely get tea brown water AND plaster stains.

 

[Charlie Bezzina]

But you can filter out the oxide in the water, thus reducing the total amount left behind right?The way I see it, if you do not sequester it you are just going to redeposit all of it again slowly. Does that sound reasonable?

 

[Katodude]

So just spitballing here. If I had a prolonged cold spell and were willing to do the AA treatment twice there might be something to this. Do the AA treatment. Shock the pool. Filter out as much as possible. You will get staining again. Then do the AA treatment again, and proceed according to the recommendations.

Its too late for me this year, as my water is back up to 71 degrees.

 

[Katodude]

Temp 71 (dont know why I am still reporting this, but it seems fun)
pH 7.6
FC 3

Pool still looks great.

Tomorrow when the pH rise to 7.7, I will drop it again to 7.2 just to make sure. Besides, I could use with another small TA drop.

On Sunday I will turn the SWG back on as I will be traveling next week. Will also add the sequestrant tomorrow.

The polyfill is not picking up anything so I might just stop that.

 

[Charlie Bezzina]

do the AA treatment twice

That's where I was leading.

I have not seen anyone purposely attempt this here, but I have bad iron staining which I'm thinking how I would attack during the winter and this is my current thinking.

 

[Katodude]

So I have been thinking about this idea of doing the AA treatment twice. The biggest problem I see (other than being not sure it will work) will be dropping the chlorine level after you shock the pool.

The idea would be do the first AA treatment, then immediately dump a bunch of Borax and Chlorine in to oxidize the iron. Use a bunch of Polyfill filters to capture as much of the iron as possible. Some will inevitably stain the pool surface again.

Then I guess you would need a bunch of peroxide to lower the chlorine level again. Of course you drop the pH and do the AA treatment again. Then sequester it until the summer where you can replace as much of the water as possible with rain.

If I had a very prolonged cold spell I guess I could do it. That might be a conversation for next winter depending on how all this works out.

In the meantime, I will keep my FC and pH at a manageable level and hope the staining does not reoccur. Oh yeah, and use some sequestrant too.

 

[Charlie Bezzina]

The peroxide may not be necessary before the second AA treatment. Let it drop by itself and keep filtering using the polyfill the whole time. Catch as much iron as you can. Do it in winter and there is no rush right.

 

[Katodude]

Well, we got an inch of unexpected rain last night. Pool level was a little low anyway, so no water replacement but it saved me from having to add any water.

I did not add any extra acid since it seems like the pH has stabilized around 7.5 - 7.6. Just going to leave it there for now and monitor.

Just added a bottle of the purple stuff. That dropped the pH to 7.4.

Going to add some more chlorine today and turn on the SWG.

Pool still looks great.

Looks to be my last report for about a week, since I am going vacation tomorrow.

 

[superuser]

I need to do this too, cold spell has my water temp down to 50F, and my chlorine levels are down around 2. I have the fittings to build a bypass pipe to get the heater out of the water circuit, so all I'm missing now is purple stuff and ascorbic acid to start.

Anyone know how much peroxide to use to neutralize chlorine? Curious how the cost would compare to just adding more AA.

 

[JoyfulNoise]

I need to do this too, cold spell has my water temp down to 50F, and my chlorine levels are down around 2. I have the fittings to build a bypass pipe to get the heater out of the water circuit, so all I'm missing now is purple stuff and ascorbic acid to start.

Anyone know how much peroxide to use to neutralize chlorine? Curious how the cost would compare to just adding more AA.

Don’t bother with peroxide. The AA will neutralize the chlorine. Just add the recommended dose.

 

[Katodude]

My FC was almost 2 when I started my treatment. Just added the AA and it went fine.

 

[superuser]

Good to hear, time to go shopping.

 

[Katodude]

Found it!!!!

Now I know where some of the iron went.

 

[Katodude]

It looks more red in person than the picture shows. Rinsed it all out.

Should I TSP soak it and then AA soak the filter to make sure I get everything out, or dont sweat it.

Pool still looks good, maybe some did precipitate on the surface but its hard to tell.

If I do another treatment next winter, I will stick some Polyfill in the filter.

 

[JoyfulNoise]

I’d leave it as is.