How to Get Rid of Mustard Algae in Pool

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How to Get Rid of Mustard Algae in Pool

Several kinds of algae can bloom in your pool, and mustard algae are one of the more common ones. With these algae in your pool, the water looks yellow and cloudy and is not very inviting.

Mustard algae are reasonably easy to remove from your pool and prevent from blooming again. All you need is to equip yourself with enough information on the algae, the right tools, and know the steps to follow when getting rid of it.

What is Mustard Algae?

Mustard or yellow algae is a member of the xanthophytes microbe family. In the USA, it is more common in southern climates in states like Florida, California, and Texas, where the weather is warmer most time of the year.

When you have these algae in the pool, it often looks more like a stain or sand, and so it is easy to miss by confusing it with other things. Also, it usually grows in the shaded parts of the swimming pool, such as the bottom and sides.

What makes mustard algae quite a stubborn problem is that it is resistant to chlorine, meaning no matter how often you sanitize the water, it will still bloom. Although it does not pose a significant danger for the swimmers, it creates a conducive habitat for E. coli and other bacteria to thrive.

How to Get Rid of Mustard Algae in My Pool Fast

What You Need

Step by Step Directions

Step 1: Remove and Disinfects All Pool Accessories and Toys

The first step should always be to remove the things that might be harboring the mustard algae in your pool and disinfect them. You have to take out all the pool toys, inflatables, and other accessories like cup holders and disinfect them.

Liquid chlorine will be perfect for disinfection, but make sure you dilute it first to avoid damaging your accessories. Also, remember to disinfect all the pool cleaning equipment you plan to use afterward, including the pool brush and your gloves.

Step 2: Brush and Vacuum the Algae

Once everything is clean and disinfected, you can start working on the pool. Here you need to make sure you have a good brush like the Greenco 20-Inch Floor & Wall Pool Brush that can scrub off the mustard algae without damaging the pool surface.

Unlike black algae, mustard algae are relatively easier to scrub off, but you need to make sure you do it thoroughly without missing any spot. When you finish, remember to allow the algae to settle before vacuuming it off the pool.

Step 3: Test and Balance Pool Chemistry

The next step is to test your pool chemistry by measuring the levels of essential parameters like chlorine, total alkalinity, and pH. When one or more of these elements is not at the right level, mustard algae get an excellent environment to thrive.

Also, you need the pool chemistry to be okay before you start adding other chemicals to your pool to get rid of the algae. Some good test strips like the JNW Direct Pool and Spa Test Strips will allow you to measure the pool chemistry fast and cost-effectively.

You should determine what you need to adjust to ensure the pool chemistry is well-balanced from your tests. For example, according to the CDC recommendations, the free chlorine level should be at least 1 ppm, while the pH should be 7.2 to 7.8.

Step 4: Shock the Pool

After balancing the chemistry, you should brush the walls and floors again and shock the pool water by adding a massive dose of chlorine. Although mustard algae are resistant to chlorine, they will not survive the high pool shock dose.

Any shock type you buy should come with clear directions on how much you need to use. However, you will need up to 3 pounds of shock to treat a 10,000-gallon swimming pool in most cases. Also, make sure you add the shock at dawn or dusk as the sun will reduce its effectiveness.

Step 5: Run Pump and Filtration System

Remember to give the shock enough time to work (up to 24 hours) and run your pump to ensure it circulates adequately.

Also, you need to keep the filtration system running to filter out any remaining algae in the water. You can run the pump and filtration up to 24 hours every day until all the algae are gone.

Step 6: Clean and Backwash Filter

You will also need to clean your filter thoroughly. Remember that the filter will trap the algae, and so you need to clean it to remove them to prevent re-blooming in the future.

Most filters will also require backwashing and several rounds of rinsing after cleaning to ensure you remove all the algae and leave them in an excellent working condition.

Step 7: Vacuum the Pool and Add Algaecide

Another step you should not forget is vacuuming the pool, as this will allow you to remove any algae still lingering in the pool so that it does not bloom again.

Once this is done, make sure you add some algaecide, as this helps prevent future blooms. Your pool should be mustard algae-free now and ready to use again.

How to Prevent Mustard Algae in My Pool

1. Ensure your pool’s pH, alkalinity, and chlorine levels are always within the ideal range through regular testing and balancing.

2. Keep other things that touch your water clean. This includes all the pool toys, ladders, slides, and all the pool cleaning equipment.

3. Practice proper sanitation techniques by using the right amount of good sanitizer and ensuring you run the pump for at least 8 hours every day.

4. Brush and vacuum your pool walls and floor at least once every week and after severe weather like heavy rain and storm.

5. Add algaecide regularly and also remember to shock the pool water often.

Bottom Line

Mustard algae leave your pool looking unsightly, and you will not even want to use it, and while it can be stubborn, it is pretty easy to remove.

Overall, dealing with these algae requires you to scrub the pool thoroughly, clean everything that touches the water, and shock it before adding an algaecide to prevent future blooms.

By doing all this and implementing the preventative tips above, mustard algae should not give you a lot of trouble.