How to Remove Stains from Vinyl Pool Liners

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Are you a pool owner looking for advice on how to remove stains from your vinyl liner? We have just the articles for you! This article will teach you everything that you need to know about removing stains from a vinyl liner. The first step is one of the most important: identifying what type of stain it is. There are three types of stains, so be sure to read this article carefully and find out which one best describes your stain.

How to Identify Pool Liner Stains

The first step to removing stains from a vinyl liner is identifying what type of stain it is. There are three types, and knowing your stain will help you know how to remove it.

  • Black) Less common than the other stains. A black stain is often connected to water siphoned from a nearby well. In this case, the stain is likely to be manganese.
  • Green, Brown) Stains with these colors almost always come from organic sources such as algae, bugs, leaves, and mud.
  • Reddish-Brown) Most reddish-brown stains are rust, but some are copper. When rust, it is usually caused by galvanic corrosion. If galvanic corrosion is your problem, the most reactive (least noble) metal will rust first. In all likelihood, that will be copper or iron in your ladders, pipes, and well water.
  • Teal (Blue-green)) Processed copper usually starts off with a reddish-brown coloration. When oxidated, the copper coloration transforms into a vibrant teal.
  • Purple or Red) If the stains aren’t from rust, the stains will likely be from berries from nearby bushes and trees. If the red is close to light pink, the stains are probably from a bacterial buildup.

There Are Test Kits That You Can Use to Identify Stains and Metals

There are also test kits that you can use to identify stains and metals on your pool liner. These will help you be sure of what type of solution is needed for the stain.

You Can Hire Professionals to Identify Stains for You

If you are unsure of what type of stain your pool liner has, then hiring professionals can be a good idea. They will charge for this service, but they will use the highest quality test kit to identify your stains and give you access to their expertise in removing them.

How to Remove Pool Liner Stains

Once you have identified what type of stain is on your pool liner, the next step to removing it will be easier. As you have probably assumed, we remove organic stains and metallic stains with different methods.

How to Remove Organic Stains from Your Pool Liner

The most difficult stains to remove are organic stains. Organic stains can be caused by algae, mold spores, or dirt that have been ground into the surface of your pool liner. Using a mixture of dish soap and bleach is one way to get rid of these types of staining agents on vinyl liners.

Step 1) Clean the Pool

These are biological stains, and the source is likely still present. Before we target the stains, we should cleanse the pool of the source of these stains.

  • Remove all debris) Leaves, sticks, and any other plant or animal life must go.
  • Vacuum the pool) There are types of vacuums that can do the job, and we have a guide on a couple of them.
  • Clean or Backwash the filters) In general, this is an important finishing step to removing algae. Algae spores can lodge themselves in filters, survive, and reinfect the pool. With that said, sand filters can be an exception to this rule.  To a point, sand filters improve as contaminants stack up against the sand. If you have a sand filter and the PSI hasn’t climbed 10 PSI above its freshly cleaned baseline, we recommend waiting to clean the filter until the stains are removed.

Step 2) Use a Soft-Bristled Brush to Loosen Algae, Dirt, and Grime

The tougher pool types can withstand a stainless-steel bristled brush. Vinyl pool liners are not tough, so we need to treat the vinyl liners with care. Use a soft-bristled brush to loosen any remaining dirt or grime on your vinyl liner.

This step is especially important if the stains are from algae. Algae spores can lodge themselves in filters, survive, and reinfect the pool. They also grow both boney and slimy coatings that protect them from harm. Without a strong scrubbing, the chlorine will not be able to penetrate and kill the algae.

It might also be a good idea to pick up a stain eraser tool. They are tools designed to brush a pool surface without damaging the surface.

Step 3) Vacuum the Pool’s Surfaces

It’s easy to mess up vacuuming the pool. It’s a simple task, but there is a method. Move too fast, and you’ll kick up the debris and make vacuuming impossible for several hours. If you use the wrong type of vacuum, you won’t have enough suction to do the job.

As we said, it really is simple. However, if you haven’t vacuumed a pool before, we recommend reading through our guide, “How to Vacuum a Pool.”

Step 4) Balance Your Pool’s Chemicals

Step 5 will require a pool shock. Balancing pool chemicals will enable the chlorine to be as effective as possible.

Step 5) Shock the Pool

Most types of stains will only require a regular pool shock. That said, algae stains might require a stronger pool shock than other types of stains. When algae overtake a pool, the recommendation is to raise the chlorine levels to 30 PPM.

You need to be careful if you raise the water to 30 PPM. Warn the household and leave some warning near the pool.

Finally, add the chlorine into the pool at sunset and turn the pool pump to “on.” Since we aren’t going to add a chlorine stabilizer, direct sunlight will rapidly evaporate the chlorine. Performing the pool shock at night will give our chlorine the time to complete its lethal work.

Step 6) Brush the Pool Surfaces Again

Same instructions as Step 2. Use a soft-bristled brush or a pool eraser tool to scrub the pool down again.

Step 7) Give Special Attention to Stubborn Stains

There are pool stain removers made specifically made for vinyl liners, and we highly recommend driving over to pick some up at your local pool shop. Since we can’t be rough with the pool brushes, stain removers can help to pick up the slack.

How to Remove Metal Stains from a Pool Liner

Metal stains are tough to remove. Here’s what we recommend:

Step 1) Check the likely sources such as ladders, rails, lights, etc.

There are two types of metal-based stains that pools encounter. Calcium scaling, plaster dust, and rust can all cover your pool in unsightly stains. If you’ve noticed or metal-based stains in one spot, you should immediately search the pool for other potential spots.

If there is rust, you might find rust inside pool pipes and around ladders, rails, and pool lights.

If you have calcium scaling, you probably have a buildup within your pool heater. If you have a saltwater generator, there will likely be some calcium buildup around the area inside the cathode and anode section of the generator.

Step 2) Deduce the Type of Stain

If can see the color of the stain, you can get a good idea of what the stain might be. For that, we’ll refer you to the color guide at the beginning of the article. If you don’t want to make an educated guess on which metal it might be, you can purchase a copper and iron kit. They’re sub-$20 for about 25 tests.

Step 3) Clean the Pool

You probably know the drill by now. Before we remove the stains, we need to deal with the sources.

  • Remove debris
  • Vacuum the pool
  • Clean the filter

Step 4) Balance Water Chemistry

Pool chemicals are interdependent. One chemical won’t work without the right amount of another chemical. That chemical won’t stay in the pool with another chemical. If you want to remove stains, you need to get the chemicals right, so everything works correctly.

While balancing the chemicals will be important in the removal of the stains, be aware that you might drain some of the water in step 6. It might change your action in this step, so we felt the need to warn you.

Step 5) Use Metal Stain Remover for the More Difficult Stains

If you are having trouble removing difficult stains, don’t use a brush with metal bristles that can damage the liner. Instead, you should consider a metal stain remover. Some metal stain removers are specially formulated to handle difficult metal stains attached to vinyl liners. 

Step 6) Replace Rusted Components and Replace Water

If a component has rusted beyond repair, replace it. While you’re at it, replacing the water might also be a good idea.

If All Else Fails, Use a Pressure Washer

If the stain is persistent, a pressure washer can probably remove it without much difficulty. The only warning we’ll give is that pressure washers can wear patterns into the concrete. We don’t have a guide for using a pressure washer, but it might be a good idea to look one up.

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