Sequestrant Question

[faby3003]

I'll start out with test results:

FC - 7
TC - 0
ph - 7.6
TA - 90
CYA - 40
CH - 200

I believe I have some Iron in my fill water, so I have been using a maintenance dose of Pro Team Metal Magic in my pool. The instructions for Metal Magic say that the sequestrant crystallizes the metal and allows it to be removed by the filter. If this is the case, does a maintenance dose need to be used, or only add the Metal Magic when I need to top off my pool?

I had some brown stains on my stairs, but removed them using a product I bought at the pool store (before I found this site, probably ascorbic acid?). So, I'm not seeing much currently for signs of staining, but want to stay ahead of the game.

 

[Melt In The Sun]

The talk about filtering out metals is not true. Maintenance doses are necessary if you have iron; why not have it tested?

 

[faby3003]

Are pool store iron tests accurate, or would I need to buy the Taylor iron test kit?

 

[Melt In The Sun]

Not sure, I've never done it. I assume that a drop test is what the pool store would use, since I've never heard of strips for iron/copper.

 

[tphaggerty]

Follow on question. I dropped one (one!!) washer in my pool when setting up this year and it rusted. Originally, the stains were images of the washer, I used asorbic acid to remove the stains from the liner. Now, the rust has redeposited in some broad swaths on the liner (very light color) and on ALL of the plastic components in the pool (skimmer frame & weir, return fittings, plastic stairs).

I plan to use a sequestrant, but was wondering if I could lower the iron content by getting the iron back in solution with asorbic acid, put a big slab of plastic in the pool to get some of the iron to deposit on it, then removing it, cleaning it outside the pool - rinse & repeat. Any chance this would reduce the iron content enough so that I don't have to dose my pool with Metal out for the rest of my life?

 

[chem geek]

You could try CuLator described here, but it hasn't yet been proven to reliably work. Results reported so far are mixed -- some OK, some not. It might work better when there is more metal in the water -- enough to show up in metal tests.

 

[rcy]

Follow on question. I dropped one (one!!) washer in my pool when setting up this year and it rusted. Originally, the stains were images of the washer, I used asorbic acid to remove the stains from the liner. Now, the rust has redeposited in some broad swaths on the liner (very light color) and on ALL of the plastic components in the pool (skimmer frame & weir, return fittings, plastic stairs).

I plan to use a sequestrant, but was wondering if I could lower the iron content by getting the iron back in solution with asorbic acid, put a big slab of plastic in the pool to get some of the iron to deposit on it, then removing it, cleaning it outside the pool - rinse & repeat. Any chance this would reduce the iron content enough so that I don't have to dose my pool with Metal out for the rest of my life?

How would you ensure that the iron would deposit on the slab of plastic and not everywhere else? Still, intriguing idea. I suppose you could do multiple ascorbic acid treatments - each time you would remove some metals on the sacrificial plastic piece.

 

[tphaggerty]

How would you ensure that the iron would deposit on the slab of plastic and not everywhere else? Still, intriguing idea. I suppose you could do multiple ascorbic acid treatments - each time you would remove some metals on the sacrificial plastic piece.

As per the 2nd part of your statement. Sort of like reducing CYA a little bit at a time. I figure there is some level at which I will no longer see the staining. Right now, the iron seems to be pretty agressive about staining the plastic, all of my white plastic bits appear to be scummy, but it is iron deposits. I'm thinking that I hang a good size sheet of plastic in the pool with more surface area than all of the other plastic combined and hope it attracts its relative % of the plating.

I'm also considering the Culator, but that thing is pretty expensive - though not compared to continuing dosing with metal out stuff.

 

[apb]

Years later just wondering if this worked? I just had the same idea after removing stains and having them reappear but not on an area where my thermometer was lying on the bottom the pool. I bought a big roll of plastic wrap and was thinking about just putting this in the pool to capture the iron that comes out of solution.