Removal of Iron Stains in the Summer?

[hdjii]

I have brown stains on my pool and suspect that is is iron because our city water has about 38 micrograms/liter of iron. I understand from reading about stain removal in the forum that the ascorbic acid process would work. I will verify the identity of the stain by testing.

My question is whether I should wait until cooler weather or proceed now in the peak heat of the summer season?

Howard

[aylad]

If it doesn't bother you to swim with the stains, I personally would wait until swim season is over, in case something comes up that requires you to close the pool for awhile.

Welcome to the forum!

[hdjii]

Thanks.

Howard

[PoolDoc]

However, if you're going to remove stains later, you might want to do some prep now.

We're finding the results aren't so good if the pool's calcium levels are high. And, lowering the calcium level can be quite a task in itself! Here's the full guide: http://www.poolforum.com/pf2/showthread.php?7923-Stain-removal-via-ascorbic-acid-treatment

[PoolDoc]

membership updated; pool data added; note pool volume correction.

[hdjii]

I am preparing to take over pool maintenance from the pool service which has been flawless. They have kept the pool crystal clear.

I have been monitoring the free chlorine and pH for a couple of weeks. The free chlorine is high (>5) after the weekly visit and declines to near zero before the next visit. The pH stays high, about 8+/-. I measured the calcium hardness at 300ppm today so I guess I should dilute the water before starting the AA treatment. We have had torrential rains, so I am surprised at the high hardness. Probably the pool guy is adding CaClO rather than NaCLO? I will be able to control this once I let him go.

I am eager to remove the stains from the pool, but I have to have control of the pool maintenance and wait for cooler weather.

[PoolDoc]

Don't even think about trying manage stains till you have K2006, and are comfortable using it. You need to be able to control your chemical levels well, as you gyrate through the various levels.

What you can do is go ahead and begin using a CuLator unit, to remove any soluble iron that is in the water. At low iron levels, if you put the CuLator under a skimmer sock, I suspect they will last indefinitely. When you fill, do so SLOWLY, through the skimmer, so the CuLator has the max chance to capture that iron.

I don't recommend adding the HEDP till your calcium is lower . . . and there's not an easy way to do this. The most effective way involves precipitating all the calcium to the bottom, and then vacuuming it up . . . but you want to remove all the free iron from the water first.

Relevant links below.

Ben

=============================================

+ We recommend the Taylor K-2006 test kit, which meets the requirements above, for many reasons. The HTH 6-way drops kit is a great starter kit, and is compatible with the K2006 (it's made by Taylor). There are a few alternatives; for example Lamotte makes an FAS-DPD kit that's OK -- but it costs 3x as much. But, we're not aware of any test that is better, and since we are all familiar with the K-2006 (and can help you with it) we recommend it exclusively ( Test kit info page (http://www.poolforum.com/pf2/showthread.php?16551) )

One caution for the 2012 season: Amazon does not stock the kits directly. So when buying at Amazon, Amato is our current preferred seller. However, they often don't list enough stock to last the whole day, so try order mid-morning. You should expect a delivered cost under $60 for the K2006A and under $95 for the K2006C. If you can't find that, wait a day.

+ Here are links to the kits we recommend (you can check local availability on the HTH kit, using the Walmart link):

HTH 6-Way Test Kit (http://www.walmart.com/ip/HTH-6-Way-Test-Kit/17043668) @ Walmart
Taylor K2006A (3/4 oz bottles) (http://www.amazon.com/exec/obidos/ASIN/B0002IXIIG/poolbooks) @ Amazon
Taylor K2006C (2 oz bottles) (http://www.amazon.com/exec/obidos/ASIN/B0002IXIJ0/poolbooks) @ Amazon


Products for metal control and clean-up:

HEDP is a dissolved phosphonate product that is pretty chlorine stable, and very good at keeping dissolved metals IN the water, instead of ON your pool surfaces. It can lift recent stains, OR it can be used along with ascorbic acid, to keep the metals in the water, after the ascorbic acid is consumed by chlorine.

Jacks Magic The Pink Stuff 1qt (60% HEDP) (http://www.amazon.com/exec/obidos/ASIN/B003MYEU3E/poolbooks) @ Amazon
20% KemTek HEDP (http://www.amazon.com/exec/obidos/ASIN/B0030BEI22/poolbooks) @ Amazon


Using polyquat during metal clean up accomplishes two things: it helps kill or prevent algae, letting you run lower chlorine levels, and it is a very good clarifier, that helps you filter out any small metal particles that may form.(Probably available from pool stores, and possibly some big box stores -- but you MUST learn to ID it correctly. See the polyquat page (http://www.poolsolutions.com/gd/polyquat.html) for more info.)

Kem-Tek 60% polyquat (http://www.amazon.com/exec/obidos/ASIN/B0030BEI0Y/poolbooks) @ Amazon
Nava 60% polyquat (http://www.amazon.com/exec/obidos/ASIN/B004BFV4EQ/poolbooks) @ Amazon


Ascorbic acid (Vitamin C) can be used to remove copper and iron stains from pool surfaces, and put the metal BACK into your pool water. (Not likely to be available locally, except as Vitamin pills.)

Ascorbic Acid Powder (http://www.amazon.com/exec/obidos/ASIN/B0013OUMVO/poolbooks) @ Amazon
Ascorbic Acid Vitamin C Powder USP Pharma Grade 11 Lbs (http://www.amazon.com/exec/obidos/ASIN/B005ISFX7O/poolbooks) @ Amazon

The CuLator product is a special patented plastic material, contained in a bag that goes into the skimmer, that can slowly take metals OUT of your pool water. We think it works, and have some evidence that it does, but not proof yet. (Not likely to be available locally.)

1 ppm Culator (http://www.amazon.com/exec/obidos/ASIN/B003C5PNUW/poolbooks) @ Amazon
1.5 ppm Culator (http://www.amazon.com/exec/obidos/ASIN/B004Y6RK3Q/poolbooks) sold by Amazon, shipped from Periodic
4 ppm Culator (http://www.amazon.com/exec/obidos/ASIN/B007AHDMTM/poolbooks) sold by Amazon, shipped from Periodic
Poolmaster 16242 Poolmaster Skimmer Basket Liner (http://www.amazon.com/exec/obidos/ASIN/B004XUIRQW/poolbooks) @ Amazon (to protect CuLator from being damaged by scum)

[hdjii]

Thanks. I think the Culator is a good idea. I will first do a bucket test to see if there are metals in the water currently. I will also do some testing with ascorbic acid on the existing stains to try to verify that it will work on my stains.

I am using the Taylor 2006 test kit. I plan to take over from the pool service and test for a while to establish a good baseline before doing anything about the stains.

[PoolDoc]

In your case, where you know your fill water has iron and have some idea of the magnitude, it's not necessary to do the bucket test. With both well and utility water metal levels will vary seasonally, and with utility water, with maintenance activities.

However, you should not be 'consuming' a CuLator pack at the rate suggested by the maker; that's why you want the skimmer sock, to maximize life.