Easy Ways to Remove Algae Stains from Vinyl Pool Liner

Algae stains are not that rare; they’re likely to be found on many pool liners due to various factors. From pH changes to pool water debris to rainwater falling in your pool, you can find that they’re pretty common.

Having the proper cleaning tools and techniques can make the cleaning process easier. Given that you don’t use the wrong chemicals or drain the pool unnecessarily, you can extend your vinyl liner’s estimated life considerably.

Together, we’ll uncover how to identify your algae stains, clean them, and reduce the chance of their return. Keep on reading to know how to remove algae stains from vinyl pool liner in detail.

What Are the Types of Algae Stains That You May Find in Your Pool?

To remove stains from your pool liner, you first have to identify the type of stain you have.

If you’re not sure whether they’re algae stains, other organic stains, or even metallic stains, you may need to buy a test kit.

Algae stains can form due to multiple reasons. You may find them after a long winter or unbalanced pool chemistry.

Here are some of the most common algae stains that you may find in your pool:

Green Algae

Green algae or light green algae stains are the most common you’ll find in your pool.

Usually, you’ll find them after rain or if you don’t clean your pool often. These algae attract bloodworms because they can feed on them, so you need to clean them regularly.

Yellow Algae

You’ll find yellow algae stains in your pool if the chlorine levels aren’t stable. They can also appear if the filter isn’t working properly.

Yellow algae can cluster on your pool liner and/or turn your pool water yellow, but they’re not dangerous, so there’s no reason to be afraid.

You can easily avoid them by testing the water’s chlorine level and making sure the filters are working.

Black Algae

Black algae stains can be particularly challenging to remove.  They are often caused by inadequate pool care, including low chlorine levels and lack of brushing.

Black algae has a root system that tends to grow within pores of uneven surfaces.  Fortunately, this means that the vinyl pools are not prone to black algae as their roots cannot grow on the smooth vinyl surface.  

Ultimately, preventative care is the best choice when it comes to avoiding black algae stains.  

How to Remove Algae Stains from Vinyl Pool Liner?

Follow these steps to make sure algae stains are completely removed from your pool.

Step 1: Wear the Safety Gear

Before starting the cleaning process, wear proper clothing, safety glasses, and rubber gloves.

This step is essential in order to prevent exposure to any dangerous chemicals. The protective gear will also help if you’re sensitive to chlorine.

Step 2: Remove Any Debris

Begin the cleaning process by removing any debris and leaves from your pool using a net.

After that, clean the filter and keep the filtration system running throughout the procedure.

Step 3: Brush the Pool Liner

To clean the pool liner, brush the surface with a soft-bristled brush or a nylon brush to loosen any algae, dirt, or other organic matter.

Be careful with this step; excessive brushing or using a harder brush could scratch the soft vinyl liner.

Ensure you brush along all crevices, including the stairs, ladders/rails, and light fixtures.  Algae likes to grow in hard to reach crevices that may not have good water circulation.

Step 4: Vacuum the Surface

Vacuum the cleaned surfaces with a liner-friendly vacuum to remove any debris left after brushing.

Step 5: Check the pH Level of the Pool

Use a test kit to check the pH level of the pool.

Usually, algae thrive in a high pH environment, so you may need to adjust the pH level of your pool before proceeding to the next step.

Step 6: Adjust the pH Level of the Pool

Add sodium bisulfate or muriatic acid to the pool to reduce the pH level. Ideally, you’ll need the pH to be between 7.2 and 7.4.

The amount of acid to add can be determined according to the manufacturer’s instructions. If not determined by the manufacturer, use swimming pool calculators to determine the correct amount relative to your pool size.

Step 7: Shock Your Pool

Add four times the required chlorine amount for your pool. This process is also known as shocking the pool. You can do it with liquid chlorine (bleach) or granular chlorine.

Be careful when adding chlorine because if you add too much chlorine in one spot, it can end up bleaching your liner patterns.  Ensure the chlorine is dissolved into the water for proper circulation.

Step 8: Check Chlorine Levels

Use a test kit to check the chlorine levels. The desired amount of chlorine needed will depend on factors such as the current cyanuric acid (CYA) level.

If you have an active algae outbreak, it will be important to monitor the chlorine levels frequently to ensure the shock has eliminated the issue.  Stable free chlorine levels indicate that the algae is no longer consuming the chlorine.

All you need to do now is to scrub any remaining algae or other organic stains. For that, use a soft-bristled brush or a nylon brush.

Step 9: Vacuum the Surfaces

Use your pool vacuum to remove any additional debris left during the process. 

Now, your pool should be clean from any stains.

What If Algae Stains Are Still There?

Stubborn stains may not be easily removed with this cleaning process. 

If not, try one of the following tips:

• Use a pool liner stain remover
• Use a stain eraser tool made for pool liners
• Use a stain test kit to confirm whether it’s algae or metal staining
• Call in a professional pool services company

How to Reduce the Chance of Your Pool Being Stained?

While staining is not an uncommon occurrence in pools, you can reduce the chance by following one or more of the following steps:

• Constantly remove any debris found in your pool
• Always check your pool chemistry and keep it balanced
• Brush and vacuum your pool once a week or after heavy loads
• Shock your pool when the chlorine levels are too low
• Try using a pool cover

Final Takeaway

Now you know how to remove algae stains from a vinyl pool liner!

You just need to brush and vacuum your pool liner thoroughly. Additionally, you may need to shock it and balance the chemical levels.

To reduce the chance of it being stained again, you should clean it regularly and always check its chemical balance. A pool cover can also help keep debris from entering the pool, which can also prevent algae growth.

Happy Swimming!