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Pool Stains: How to Find and Remove Them

When it comes to enjoying your swimming pool, the last thing you want are pool stains. Pool stains can happen to any pool for a variety of reasons. In order to address the problem you must first discern whether the stain is a metal/rust-based stain or an organic stain. Metal or rust-based stains are caused when metals are accidentally introduced into pools from well water or corroded copper pipes. An organic stain is indicative of environmental debris, like leaves or berries settling to your pool surfaces; thus staining them..

What does your stain mean?

To tell whether the stain is caused by metal or an organic substance you can simply look at its colour. Let’s take a closer look at what each colour of stain indicates.

  • Green and brown stains are usually caused by organic factors like leaves and other plant matter.

  • Red and blue stains are usually indicators that some type of berry has fallen into your pool. Be sure to check your pool area and surrounding area for the culprit.

  • Blue, green and black stains are harder to discern. First check to make sure this is not from any residual organic matter around. If you cannot find the organic culprit, this type of stain is likely to be from copper.

  • Green, brown and red stains are a combination that is indicative of iron being present in the swimming pool.

  • When you see brown, black and purple stains this combination is indicative of manganese being in the water.

Testing the Stain

Now that you have identified whether your stain was a metal, rust-based, or an organic stain, you need to confirm it is the source of the problem. For organic stains you can simply add a small amount of chlorine directly to it, and it will wipe away easily once chlorine has been applied. Metal stains do not react as well to chlorine. You will want to use what is called ascorbic acid. Ascorbic acid is found in citrus juices with a lot of vitamin C. Therefore just crush a few vitamin C tablets and apply them to the stain. If the vitamin C does not remove it, it should at least lighten it. Now that your test has confirmed that the stain is indeed organic or metal, let’s look at how to rid your pool of such stains.

How To Get Rid of Pool Stains

When it comes to an organic pool stain, the best way to rid your pool of them is by super chlorinating the water, then For best results you should shock your pool at dusk or at night. To do this you will want to add 3 pounds of calcium hypochlorite pool shock for every 10,000 gallons of water. Once you shock your pool, thoroughly brush the stains the next morning and let the pool circulate until dusk. Continue brushing and using chlorine until the stains are gone.

[When it comes to a metal stain in your swimming pool, the fix may not be as easy. You will need to take a water sample to your local pool professional to determine the actual problem. The test will look to see exactly what kind of metals and how much are in your pool. Upon test results, your pool professional will suggest a special additive for your pool that will work to remove metal stains. Once you have your chemicals add them to your swimming pool, according to manufacturer’s instructions. Brush the stain to aid this process. If chemicals and brushing have not worked to remove the stain, you may need to look into a more specifically targeted citrus-based stain remover. These targeted formula are also available from your local pool care professional.

How to Prevent Pool Stains from Coming Back

Preventative measure will need to be taken now that your pool is prone to stains. For continued prevention against organic stains you will need to ensure that you keep the correct level of chlorine in the pool at all times, and maintain the balance of pH and alkalinity.]( "DPS Pool Cleaners") Regularly vacuuming your pool and skimming the surface of the water for debris will also help fight against organic stains.' For continued prevention against metal stains you should regularly test your pool water for any metals. This should help aid against stopping metal stains before they form. If you are prone to metal stains be sure to consult your local pool care professional about using a stain and scale product as part of your regular pool maintenance. Continue to keep your chemicals balanced, and regular brushing, as low pH levels can cause copper pipes to corrode, leaving you with more metal stains. If you find yourself plagued by pool stains, you’re just one of many homeowners who are. is here to help, offering a wide array of specialty chemicals to help optimize your swimming pool's water and prevent stains.

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