THE SCIENCE OF CuLATOR

What is CuLator?
CuLator® Metal Eliminator and Stain Preventer is a technologically advanced polymer product designed to rapidly eliminate metals from fresh and salt water. CuLator takes conventional chelating or sequestering agent groups and binds them to a unique, insoluble and non-toxic polymer backbone. This allows metals to be physically removed and eliminated from pool, spa or fountain water, rather than temporarily sequestering metals in the water. The chemistry to produce these polymers was developed over 25 years of scientific research.

How does CuLator work?

 

What metals will CuLator eliminate from pool water?
CuLator removes and eliminates many stain-causing metals from pool and spa water including: iron, copper, manganese, cobalt, nickel, silver and lead.

How do metals get into the pool water?

  • Source water
  • Metal-based (usually copper or silver) algaecides
  • Ionizers (mineral-based water purification systems)
  • Rain run-off
  • Pool equipment
  • Fertilizers
  • Iron from salt used in salt water systems
  • Water from a sprinkler
  • Decking, natural stone, and faux stone water features
  • Concrete and pool surface

Why is CuLator® different than conventional sequestering agents?
Conventional sequestering agents surround the metal ions and slow down the oxidation and precipitation of metal oxides onto the pool surface. Unfortunately, sequestering agents are unable to remove significant amounts of metals through a pool’s filtration system. Furthermore, all sequestering agents break down over time and need to be constantly added to the pool water. Many sequestering agents are also phosphate-based.

CuLator Metal Eliminator and Stain Preventer is the world’s only true metal eliminator. Developed for the Environmental Protection Agency’s (EPA) Superfund Program, these polymers are the only compounds that do not dissolve in water; they are also the only such compounds that rapidly bind and eliminate metals. Metals are bound to the polymer and trapped in the CuLator cloth bag (placed in a pool skimmer basket or pump basket with protective GatorEgg) and not left floating in the pool water. After use, the bag is thrown away and the metals permanently eliminated.

Is CuLator® non-toxic?
CuLator Metal Eliminator and Stain Preventer is non-toxic and is totally compatible with all sequestering agents. CuLator is also compatible with biguanides and all mineral-based water purification systems that release small amounts of minerals (such as copper, silver and zinc) into the pool water. CuLator Metal Eliminator and Stain Preventer is effective over a very broad pH range (pH 4 to 14), and works in fresh water, excessively hard water, and salt water.

What Causes Metal Stains In Pools?
Joseph P. Laurino, PhD, MBA

Nothing bothers pool owners more than those unsightly blotches and discolorations on an otherwise unblemished pool surface. Staining is caused by organic matter such as algae, inorganic metals, or water trapped beneath plaster surfaces. Managing and preventing stains, especially those from metal oxidation, can be challenging.

Organic stains are typically removed by a simple shock treatment followed by scrubbing the surface with a stiff brush. However, many organic stains, such as those caused by some types of algae, require more complex treatments including enzyme-based pool chemicals and/or metal-based algaecides. Pool owners should consult their local pool professional to determine the cause of the organic stain and the best treatment. If a metal-based algaecide is required, always use a sequestering agent to prevent the metal from oxidizing and staining the pool surface, and use CuLator® Metal Eliminator and Stain Preventer to remove and eliminate the metal from the water.

Stains resulting from metal oxidation are frequently more problematic than those caused by organic material. Metals are naturally occurring substances found everywhere, including stone, soil and water. Rainwater is acidic and tends to dissolve the metals found in soil and stone, thereby increasing metal concentrations in surface and ground water. Furthermore, because all municipal and well water contains some metal, introducing metals into your pool is unavoidable. Irrigation systems are also a common source of metal contamination.

Additionally, stone water features, decking materials, plaster pool surfaces, pool chemicals, pool equipment, and lawn fertilizers are all potential sources of metal contamination. Marble, flagstone and granite, for example, naturally contain iron, which can leach into a pool after every rain. Salt used in all salt water systems also contains iron. Copper can be introduced into pool water from the heat exchanger found in the pool heater, from copper-based algaecides, or from poorly maintained ionization systems. Manganese and nickel, also commonly found in pool water, are frequently in the source water used to fill pools.

All content © 2013 Periodic Products Inc.

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How Are Metal Stains In Pools Removed?
Joseph P. Laurino, PhD, MBA

Most metal stains can be removed from plaster, fiberglass or vinyl pool surfaces. The chemistry to accomplish this, however, is fairly complex and should only be done in consultation with a pool service professional knowledgeable in metal stain removal. The steps outlined below represent an overview of the process and should not be viewed as a detailed description of the stain removal procedure.

Step 1: Determine the cause of the stain. Pool stains are caused by organic material (such as algae, leaves or other plant debris), metals, or water trapped beneath the plaster surface. Use a stain ID kit to determine whether the stain is caused by metals, and if so, which type of metal is causing the stain.

Step 2: Eliminate any metal in the pool water. Place a CuLator® Metal Eliminator and Stain Preventer PowerPak 1.0 in the skimmer basket or a CuLator®  Metal Eliminator and Stain Preventer Ultra Powerpak 4.0 in the pump basket three to four days prior to starting the stain treatment. This will begin the process of eliminating any metals that are in the pool water, and will greatly speed up and simplify stain removal and subsequent metal elimination.

Step 3: Prepare your pool equipment. Turn off all automatic chlorinators, chlorine generators, UV systems, ozone generators and metal ionizers. If possible, bypass all pool accessory hardware, such as pool heaters, chlorine generators and other non-filtration systems in contact with the pool water.

Step 4: Remove the stain from the pool surface. Use a stain removal product to release the stain from the surface of the pool. These chemicals typically contain ascorbic acid, citric acid, oxalic acid, or a combination of two or all three. Follow all label directions carefully, making sure to wear appropriate protective clothing and face protection. These stain removal products will immediately react with the free chlorine in the pool water. Because of this, chlorine levels should be brought down below 1ppm prior to the addition of stain removal products. (NOTE: Because free chlorine levels are kept very low during this entire process, stain removal is not recommended during warm or hot temperatures, as this favors the growth of algae.)

Step 5: Measure the level of metals in the pool water. After the stains have been removed, use a “total” metal test kit to measure the level of metal in the pool water. It is imperative that both free and complexed (sequestered) metals be measured when determining the total metal concentration (metal load) of the water. Make certain the metal test kit contains a releasing agent that is added to the water sample. (NOTE: The EZ-DX® Digital Pool Water Test Kit easily and accurately measures total copper, total iron, and manganese levels in pool water.)

Step 6: Balance the pool water. Restore pH, alkalinity and hardness levels to their ideal ranges.

Step 7: Use a sequestering agent to temporarily protect the surface. Sequestering agents are soluble metal chelators that are added in liquid form to the water; these temporarily protect the metals from oxidizing on the pool surface. Contrary to popular belief, sequestering agents only temporarily tie up dissolved metals and prevent them from oxidizing onto pool surfaces. Sequestering agents do not effectively remove or eliminate metals from the water; however, it is still important to use them in your metal control regimen. Sequestering agents provide needed “insurance” by allowing for the addition of small amounts of chlorine; they also allow limited use of the pool while other methods are employed to eliminate the dissolved metals from the water. NOTE: DO NOT shock the pool with chlorine for three to four weeks. Add sufficient chlorine or other sanitizer/oxidizer to keep the level of free chlorine between 1-2 ppm. (NOTE: The reaction of chlorine with the excess stain removal product frequently results in cloudy water. This is only temporary and will resolve in one to two days.)

Step 8: Eliminate metals from the pool water. The final step in this process is to reduce the level of metal in the pool water to below 0.1 ppm. If only sequestering agents are used to treat staining, the stains will return in three to four weeks unless you continually add more sequestering agent and avoid high chlorine and pH levels. Therefore, it is important to eliminate the metals from the water using CuLator Metal Eliminator and Stain Preventer. CuLator is the world’s only insoluble polymer that rapidly and permanently binds metals and physically eliminates them from both fresh and salt water.

Using the level of metal measured in Step 4, determine the appropriate number of CuLator PowerPak 1.0 or CuLator Ultra PowerPak 4.0 products to use. The PowerPak 1.0 product eliminates 1.0 ppm total metals from a 20,000 pool, while the Ultra PowerPak 4.0 eliminates 4.0 ppm total metals from a 20,000 pool. CuLator Metal Eliminator and Stain Preventer is very easy to use. The polymer is contained in a cloth bag that is placed in the skimmer basket or in a cartridge placed in the pump basket. As the water passes over the polymer, metals are quickly absorbed and eliminated. After 30 days, the bag is simply discarded along with the metals. The CuLator polymer does not dissolve in the water, impact the hardness of the water, or add phosphates; it is also non-toxic and does not interact with other pool chemicals or systems.

Step 9: Maintain balanced pool water. Upon completion of this process, confirm that your pH, alkalinity, hardness and chlorine levels are within the ideal range. Turn on all automatic chlorinators, chlorine generators, UV systems, ozone generators and metal ionizers. Place a fresh CuLator PowerPak 1.0 in the pool skimmer basket (or a CuLator Ultra PowerPak 4.0 inside the pump basket cartridge) to keep metal levels low and help maintain a stain-free pool throughout the season.

All content © 2013 Periodic Products Inc.

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Are Metal Stains In Pools Preventable?
Joseph P. Laurino, PhD, MBA

Most metal staining is preventable. The best way to control metal staining is to take a proactive approach rather than waiting for problems to occur. This can be done by following four easy steps:

Step 1: Balance pool water. Because poor water chemistry will eventually destroy pool equipment and surfaces in any pool, maintaining the correct pH, alkalinity and hardness of pool water is always the first step to prevent metal stains. The most significant factor in preventing metal stains – and often the most overlooked – is pH. Pool water can look clear even at very high or very low pH levels, but this is no accurate indicator of metal contamination. Pool water with a low pH (less than 7) is acidic, and can actually dissolve metals found in pool equipment and heat exchangers. Acidic pool water will also dissolve stone and brick materials used around the pool, as it will the pool’s plaster surface, resulting in more surface pitting and etching and the release of imbedded metals into the water.

High pH levels (greater than 8) cause metals to “plate out” of the water and form metal stains. If pool water does not contain enough carbonate (alkalinity) or calcium (hardness), it will draw these materials out of the plaster surface, dissolving it in the process and causing even more etching, pitting and release of the metals naturally found in plaster into the pool water.

Unfortunately, maintaining balanced pool water only delays the onset of metal stains. Metals are constantly being added to the pool water from multiple sources, and unless they are eliminated from the water, staining will eventually occur – even in pools with properly balanced pool water.

Step 2: Measure the level of metals in the pool water. Many metal test kits are available for the home and commercial pool market, but the vast majority of these only measure the free form of dissolved metals. Dissolved metals typically exist in two forms: the free form, and the complexed or sequestered form. It is absolutely essential that both forms are measured when determining the total metal concentration of pool water. Make certain the metal test kit contains a releasing agent that is added to the water sample. Generally, common liquid dropper or strip format tests involving one-step procedures only measure “free” metal concentration, while two-step testing procedures measure “total” metal concentration. Periodic Products’ EZ-DX® Digital Pool Water Test Kit easily and accurately measures these desired total copper, total iron and manganese levels in pool water.

It’s important to note that oxidized metals that have already stained pool surfaces are not measurable by any pool water test. While the exact amount of metal that can remain dissolved in water depends upon numerous factors – including the type of metal, the water chemistry, the total dissolved solid (TDS) content, and the amount of oxidizer present – total metal concentrations exceeding 0.3 ppm frequently result in surface staining.

Step 3: Use a sequestering agent to temporarily protect the pool surface. Sequestering agents are liquid soluble metal chelators added to pool water to temporarily protect pool surfaces from oxidizing metals. There is widespread misunderstanding in the pool and spa industry regarding the use and effect of sequestering agents. Sequestering agents have been used in municipal water treatment facilities for decades and require highly sophisticated filtration systems for the removal of sequestered metal particles. The size of these sequestered metal particles is simply too small to be effectively removed by pool filtration systems. (The only exception occurs during pool start-ups. When plaster dust from the pool surfaces mix with the sequestering agents, metals tend to stick together in larger particles. Depending on the size of these particles, some – but not all – may be large enough to be removed by the pool filtration system; the smaller particles will simply pass through the filter and return to the pool.) Sequestering agents, therefore, only temporarily bind with dissolved metals to prevent them from oxidizing onto pool surfaces; they do not effectively remove or eliminate metals from the water, and metal stains will inevitably occur.

It is still important to use sequestering agents in your metal control regimen, as they provide needed “insurance” by allowing for the use of the pool while other methods are employed to eliminate the dissolved metals from the water.

Step 4: Eliminate metals from the pool water. The final step – and the most effective – is to reduce the concentration of metal in the pool water. Until recently, there was no safe or efficient way to eliminate metals from pool water short of replacing the metal-contaminated water with new metal-free water – an impractical and costly solution for most pool owners. A new procedure involves using an insoluble chelating polymer product to remove and eliminate dissolved metals from pool water.

There is only one such product available on the market: CuLator® Metal Eliminator and Stain Preventer. CuLator Metal Eliminator and Stain Preventer is an insoluble chelating polymer that rapidly and permanently binds to dissolved metals to that they can be physically eliminated from pool water. The polymer is contained in a cloth bag that is either placed in the skimmer basket, or housed in a cartridge placed in the pump basket. As pool water passes over the polymer, metals are quickly bound, absorbed and eliminated from the water. After use, the bag is simply discarded – and with it, the metals.

The CuLator polymer is pre-measured, easy to use, and works in both fresh and salt water. The polymer does not dissolve in water, impact the hardness of the water, or interact with other pool chemicals or systems. CuLator Metal Eliminator and Stain Preventer is also non-toxic and does not add phosphates to the water.

Conclusion: By following these four simple steps – keeping your pool water balanced, measuring the total level of metals in the pool water, using a sequestering agent for temporary stain protection, and eliminating the metals from the pool water with CuLator Metal Eliminator and Stain Preventer – it is possible to enjoy years of stain-free pool ownership.

All content © 2013 Periodic Products Inc.

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How Does CuLator® Eliminate Metal Staining Problems?
Joseph P. Laurino, PhD, MBA

CuLator® Metal Eliminator and Stain Preventer is a technologically advanced product designed to rapidly eliminate metals from water. CuLator takes conventional chelating or sequestering agent groups and binds them to a unique, insoluble and non-toxic polymer backbone. This allows metals to be physically eliminated from pool, spa or fountain water, rather than simply sequestering metals in the water. The chemistry to produce these polymers was developed over 25 years of scientific research.

Conventional sequestering agents surround the metal ions and slow down the oxidation and precipitation of metal oxides onto the pool surface. Unfortunately, sequestering agents are unable to remove significant amounts of metals through a pool’s filtration system. Furthermore, all sequestering agents break down over time and need to be constantly added to the pool water. Many sequestering agents are also phosphate-based.

CuLator Metal Eliminator and Stain Preventer is the world’s only true metal eliminator. Developed for the Environmental Protection Agency’s (EPA) Superfund Program, these polymers are the only compounds that do not dissolve in water; they are also the only such compounds that rapidly bind and eliminate metals. Metals are bound to the polymer and trapped in the CuLator cloth bag (placed in a pool skimmer basket or pump basket with protective GatorEgg) and not left floating in the pool water. After use, the bag is thrown away and the metals permanently eliminated.

CuLator Metal Eliminator and Stain Preventer is non-toxic and is totally compatible with all sequestering agents. CuLator is also compatible with biguanides and all mineral-based water purification systems that release small amounts of minerals (such as copper, silver and zinc) into the pool water. CuLator Metal Eliminator and Stain Preventer is effective over a very broad pH range (pH 4 to 14), and works in fresh water, excessively hard water, and salt water.

The amount of CuLator Metal Eliminator and Stain Preventer required to eliminate metal staining problems is dependent upon the level of metal in the pool. As with all pool chemistry, testing the water is the only way to know the amount of metal in the pool. Use a metal test kit that measures total metal levels (such as the EZ-DX® Digital Pool Water Test Kit), not just “free” or non-sequestered metals. This is especially important if sequestering agents have been added to pool water. One CuLator PowerPak 1.0 will eliminate 1.0 ppm total metals from a 20,000 gallon pool, while one CuLator Ultra PowerPak 4.0 will eliminate 4.0 total metals from a 20,000 gallon pool.

The best way to control metal levels in pool water and avoid metal staining is to take a proactive approach. All municipal and well water used to fill pools contains some metal, and so it is impossible to avoid introducing metals into pool water. Other sources metal contamination include stone water features, pool decking materials, plaster pool surfaces, and many algaecides. CuLator Metal Eliminator and Stain Preventer is the only effective way to eliminate metals from the water and prevent metal staining from occurring. For more information on the sources of metal in pool water, see our Technical Bulletin: What Causes Metal Stains in Pools?

While CuLator is not able to remove existing metal stains from pool surfaces, it is a necessary final and important step in all stain removal processes. To learn more about stain removal and pool surface remediation, see our Technical Bulletin: How Are Metal Stains in Pools Removed?

All content © 2013 Periodic Products Inc.

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Pool & Spa News June 28, 2013
Getting the Stains Out
The key is to take action before problems appear
By Joseph P. Laurino

The causes of pool stains are no mystery: organic material, such as algae and tannins from plants, or inorganic material, such as metals, has become attached to the pool surface. Additionally, plaster pools can have grayish staining caused by occluded water (sometimes called hydration staining). But while the causes might be easy to understand, dealing with stains is more challenging. There is a lot of unsubstantiated information on the subject, particularly relating to metal stains and how to treat, remove and prevent them.

All pool water contains metals. Some sources of dissolved metals are familiar: fill water, pool chemicals, deteriorating pool equipment, lawn fertilizers and other chemicals in rain runoff. More recently, the increased use of stone, brick and marble in and around pools has added to the levels of dissolved metals in pool water. This is because of the acidic nature of rainwater, which typically has a pH of 5.0 to 5.6, but sometimes as low as 1.8 in highly populated areas. Acidic rainwater releases the metals found in these materials. Marble, flagstone and granite, for example, naturally contain iron which can leach into a pool.
Balanced pool water is essential. Poor chemistry in any pool, regardless of the water source, can eventually destroy pool equipment and surfaces. By its chemical nature, pure water is very corrosive. This point is especially important for owners of plaster pools to understand because if the water does not contain enough carbonate (alkalinity) or calcium (hardness), it can impact the plaster.
Nor are vinyl pools immune: Severely unbalanced pool water can leach the plasticizer (the chemical added to vinyl to give it flexibility and elasticity) out of vinyl liners.

pH is the most significant factor in preventing and removing stains, and is often overlooked because pool water can look clear even at very high or very low pH levels. Pool water with a low pH can dissolve the metals found in pool equipment and heat exchangers. And just as the stone and brick used around the pool can dissolve in acidic water, so too will the pool’s plaster surface, resulting in more surface pitting and etching and the release of embedded metals into the water. At the other end of the pH spectrum, high levels cause metals to “plate out” of the water, or form stains at the molecular level that discolor pool surfaces.

Pools with high total dissolved solids are especially problematic for controlling stains because the salt content of the water is naturally high. Salt water is corrosive. Additionally, chemical compounds frequently behave differently in high salt solutions. To add to the problem, there is a growing body of evidence suggesting that plaster surfaces may be more soluble in salt water than in fresh water. Salt water pool owners, and those who service them, need to be especially diligent in monitoring water chemistry.
Unbalanced water can facilitate the release of metals and surface staining, but what’s also true is that even pools with balanced water will eventually stain. Since metal levels in pool water are constantly rising, the water eventually becomes saturated. Dissolved metals are then released onto pool surfaces, resulting in stains. In order to minimize metal staining, it is important to determine the concentrations of various metals in the water (or “metal load”), protect the metals from oxidizing on the surface of the pool, and reduce the concentration of the metals in the water.

Metal tests properly conducted with precisely calibrated scientific instruments are very accurate. But common liquid dropper and strip format tests, while convenient and affordable, have limitations. Sequestering agents and other chemicals interfere with these tests, frequently showing metal levels that have tested significantly lower than they actually are. When testing for metals, make certain the kits contain a releasing agent, and are measuring total and not just “free” metal concentrations. In general, two-step metal testing procedures measure total metal concentrations, while one-step procedures measure only free metal concentrations.
Once you know the metal load of the pool water, you need to take action to minimize staining. One effective temporary measure is to add a sequestering agent. These chemical compounds tie up the dissolved metals and prevent them from oxidizing on the pool surface. Unfortunately, sequestering agents do not effectively remove metals from pool water, and they break down over time, losing their ability to bind metals.

Unfortunately, the molecular size of sequestered metals is too small to be effectively filtered under most conditions. Efficient removal of sequestered metals requires highly sophisticated filtration systems. The typical pool filtration system is able to remove only relatively large particles, which means that most, if not all, of the time, sequestered metals pass through the filter and return to the pool.

In studies performed in our chemistry laboratory using filters equivalent to or better than those found in the best pool filtration systems, sequestering agents removed less than 5 percent of dissolved copper from properly balanced water. While somewhat better results were obtained with dissolved iron (ranging from 50 percent to less than 1 percent removal), significant amounts of iron remained in the water. One notable exception was with liquid sequestering agents and plaster dust. These materials tend to stick together to form larger particles. Depending on the size of these particles, they can be removed by many filtration systems. Even under these circumstances, some metals will remain in the water, often in significant amounts.

Ultimately, to prevent metal staining, the concentration of metal in the pool water must be reduced. This can be accomplished in one of three ways. One option is to dilute the metals by removing some of the existing pool water and replacing with fresh metal-free water. This is often not possible due to either the lack of metal-free water or the cost associated with water replacement. A second option is to use an ion exchange resin system to remove the metals from the water. This process, while relatively straightforward, tends to reduce the calcium concentration of the water, thereby requiring the addition of calcium compounds to restore the proper hardness to the water. A third choice is to use a newly developed insoluble chelating polymer to remove the metals from the water. This material is easy to use, does not impact the hardness of the water, and does not interact with other pool chemicals.
The best way to keep pools free from metal stains is to take a proactive approach rather than waiting for problems to occur. Use fill water relatively free of metals, keep pool water properly balanced, and regularly use effective metal control and eliminating agents.
Laurino, Ph.D. MBA is the founder and president of Periodic Products, located in Fort Lauderdale, Fla., and the inventor of the company’s polymer technology.

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WHY do I need CuLator Metal Eliminator?

All water has metals!  Metals cause stains!  Metals also cause discoloration of pool and spa water!

Did you know metal staining begins at .3 ppm?

CuLator is the only way to get metals out of water without draining.  When metals bind to the polymer inside the bag, (PowerPak) they do not release back into the water.  After treatment, those metals are contained inside the bag and are disposed of in your trash.

WHEN do I need CuLator Metal Eliminator?

When a pool or spa has water!

  • When there are metal stains present (first remove stain with an acid stain treatment).
  • When using a stain treatment to remove metal stains (the CuLator will catch what was on the walls).
  • When using a copper or silver (metal) based algaecide.
  • When using any sequestrant (Metal Out, Metal Free) because sequestrants are a temporary fix.
  • When using a salt water pool or chlorine generator (salt always adds iron).
  • When you fill or top-off the pool with well water.
  • When you have any water run-off that enters the pool.
  • When using a copper heating system (especially when your pH has gone too low).
  • When using an ionizer.
  • When using a “Mineral” water purification system (Nature 2, Frog, or PoolRx).
  • When there are faux rocks, water features, bricks or stones around the pool.
  • When your irrigation system sprays water into your pool.
  • When you start up your pool (have your builder use a CuLator Ultra 4.0).
  • When your blonde hair turns green after swimming (that is copper!).

Here is a more scientific guideline for using CuLator for the Pool Geeks (you know who you are…):

Use CuLator When:
Stains:                            Present
Acid/Base Demand:       > 8
pH:                                 < 6.8
Alkalinity:                        < 20
Algae:                              Present
Calcium:                            ideal
Copper:                            > .3
Iron:                                 > .3
Manganese:                    > .3
Nickel:                              > .3

HOW do I use CuLator Metal Eliminator?
CuLator may be placed into your skimmer basket:

culator

or pump basket (only with a GatorEgg plastic protector):

metal in pool water

CuLator is best when changed monthly.  However, depending on the level of metal and size of the pool, it may last longer. Placing a CuLator bag onto a chlorine puck in the skimmer basket will shorten the life span of a CuLator PowerPak.

HOW MUCH CuLator Metal Eliminator do I use?

That all depends on:

  • Size of your pool.
  • How much metal is in the water.  Note: Free metal tests don’t give you the full picture if you are using a sequestrant…make sure you ask for a TOTAL metal test.)
  • How much metal you are adding to the water (You must discover the source of the metals such as salt, ionizer, irrigation system, heater, algaecide…).

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