Stains on Swimming Pool Surfaces Due to Metals


Most, but unfortunately not all, staining on pool surfaces are preventable.  The problem is most people don’t realize they have metals in their water.  Even  trace amounts of these metals (iron, copper, manganese, cobalt, silver) can  cause staining.  In fact there’s enough copper in ONE penny to completely stain  an average sized swimming pool!  Obviously, the conditions have to be right.   This is where prevention & good, proper pool care come into play.

Here’s what happens:  metals come into your pool whenever fresh, make-up  water is added.  They’re dissolved in the water.  Whether it’s municipal water  or well water, metals can be present.  As the metals accumulate, the greater the  chance that they will eventually come out of solution.  Once out of solution,  they make the water cloudy or worse, they “plate out” on the pool’s surfaces & stain.  Metals can come out of solution through a variety of ways.  But  there’s 2 that typically happen.

When a pool is shocked whether with chlorine or a non-chlorine oxidizer, the  shock oxidizes everything in the water, including metals.  Oxidized metals  become “rust” in the case of iron or “Verdi gris” in the case of copper.

In the second way, metals come out of solution or are left “exposed” when the  pH, Total Alkalinity and/or Calcium Hardness are left unchecked & allowed to  go low (pH below 7.2, Total Alkalinity below 80 ppm [non-Pristine Blue pools],  Calcium Hardness below 100 ppm).  The water becomes aggressive & the metals  are more susceptible to oxidation.  In many cases, pool-owners don’t properly  test their water & more likely rely on the “look” of the water (the water’s  clear, everything must be alright).  This is typically the case with blonde hair  turning green – low pH helps bring copper out of solution & “plates” it out  on the person’s hair!  Then people blame the chlorine!  It’s the copper in the  water.

When it comes to testing, remember that you can only test for metals when  they are in solution.  Once oxidized, the metals come out of solution &  cannot be tested.  That’s why once a metal stain has occurred, the metal test  will NOT show any metals present.

Here’s how to prevent metal stains:

Keep the water balanced. pH 7.4 – 7.6; Total Alkalinity 125 – 150 ppm (vinyl  pools), 80 – 125 ppm (plaster / gunite pools) (Please note that these TA values  ARE NOT applicable in Pristine Blue treated pools where the TA is to be  maintained at no higher than 80 ppm); Calcium Hardness 200 – 250 ppm (vinyl  pools), 225 – 275 ppm (plaster / gunite pools).  In other words, have your water  professionally tested at opening, mid-season & at closing (at least) – make  sure they do a copper & iron test.

Prevent metal stains by using BioGuard Pool Magnet (a sequestering agent) or  Jack’s Magic Pink Stuff or Blue Stuff when filling the pool then adding a  maintenance dosage monthly.

If you have well-water, treat automatically with Pool Magnet or Jack’s  Magic.

If you have municipal water, Pool Magnet or Jack’s Magic won’t hurt.

In areas of High Calcium Hardness, regularly treat the pool with products  such as BioGuard Scale Inhibitor to prevent staining and scaling due to excess  dissolved calcium in the water.  This type of staining can result in what is  often times referred to as “plaster mottling.”  Plaster mottling is a condition  with newly plastered pools where the plaster looks “streaky”.  There is almost  no way to prevent from happening because of the differences of water sources,  plaster “formulations”, environmental conditions, etc.  In other words, the pool  guy didn’t do it!  It’s a condition that can and does happen.

If it’s too late & you already have staining:

1. Get the water balanced.  Keep in mind that further discoloration COULD  occur.  This is a temporary phenomena & will clear once the treat process is  complete.

2. For light staining of iron & copper, use BioGuard Pool Magnet at a  rate of 1 qt. per 10,000 gallons of water.  BioGuard Pool Magnet works well on  “fresh” stains.  Avoid shocking the pool for about 3 days.

3. For heavy staining, Jack’s Magic Blue Stuff is an excellent product.   Jack’s Magic products are preferred because you can have high or higher amounts  of chlorine present (in excess of 10.0 ppm).  This is especially important when  treating metal problems PLUS chlorine demand or algae problems.  You can treat  both at the same time.  Follow this up by using a product like BioGuard Sparkle  Up which can physically remove the heavy metals from the water.

4. For light to medium staining on pool steps BioGuard Stain Remover is a  good product.

5. Heavy metal staining on vinyl, fiberglass or acrylic steps can be treated  with Jack’s Magic Step Stuff.

6. Save yourself time, money & effort using Jack’s Magic Stain ID Kit.   It really helps in identifying the exact metal that’s causing the stain.

7. Keep in mind that when treating metal stains, the staining may not lighten  or be “removed” for several days to several weeks, especially if the stains are  “old”.

Article Source: http://EzineArticles.com/1279920

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