01/14/2020 | Swimming Pool & Spa | 9 MINUTE READ

How to Identify, Treat, and Prevent Pool Algae

Home pool overlooking coastline

Algae is a unique plant form that’s comprised of a single cell. It uses the process of photosynthesis to create its own food, which means that it can continue to grow and develop solely by having access to sunlight. Because of how tiny these plants can be, you won’t notice them in your pool until several million have accumulated. The growth of algae is particularly rapid during the hot summer months of July and August.

The most effective way to get rid of algae growth is by preventing algae in the first place. If you ever notice algae in your pool, you should treat it before you and any other members of your home swim in it. To begin, once you’ve scrubbed the pool and have turned on the water filter, you will need to wait at least 24 hours for the water to be properly filtered. It is also possible that you will need to treat the pool several times before all of the algae is eliminated. This means that it could take upwards of a week to eliminate the algae in your pool depending on how extensive the issue is. The following article will provide you with an in-depth guide on how to effectively identify, treat, and prevent pool algae.

What Problems Can Algae Cause?

Before going into the many problems that algae can cause, it’s first important to understand that not all algae is harmful. However, even the non-harmful algae can be unpleasant to the eye, which is why it’s always recommended that you clean your pool immediately after detecting algae. One of the main issues that algae causes once it develops in a pool is that people won’t want to swim in your pool once they see it. Whether the algae is black, green, or yellow in color, all of these colors will make the appearance of your pool unseemly.

Whether you clean the pool yourself or hire a professional cleaner, it can also be very costly to treat a pool where algae has developed. In order to avoid this problem, it’s much better to take steps to prevent the development of algae. Likely the most frustrating of issues caused by algae is that a large algae bloom makes it more likely that future blooms will occur. This means that treatment costs will increase as well.

Even though algae isn’t exactly dangerous on its own, it can harbor harmful bacteria that can adversely affect your health. An example of this harmful bacteria is E. coli, which can lead to diarrhea, cramping, and nausea. Algae is also known to clog up filters and other pool equipment, which means that you will be required to spend a significant amount of time cleaning these items and pieces of equipment.

Algae bloom

How Do Algae Blooms Occur?

If small amounts of algae are left untreated, it’s possible that large algae blooms may develop in your pool. This occurs whenever the water in your pool isn’t perfectly balanced. If the nutrients in the pool water aren’t at the proper level, algae will start to form and eventually grow out of control. While algae most commonly occurs when a pool owner doesn’t clean and maintain their pool, it’s important to understand that even well-maintained pools can eventually develop algae blooms. The main reasons why algae blooms happen include:

  • Not having enough chlorine in the water
  • Shaded areas around the pool
  • A pH imbalance of some sort
  • Warm weather
  • Cold weather
  • Filter circulation problems

Some of the bio contaminants that can get blown into your pool and bring about the development of algae include dirt, rain surface runoff, leaves, and bird droppings. If the chlorine levels in your pool are too low, algae will start to develop. Low chlorine levels are usually accompanied by higher pH levels, which means that the chemical composition of your pool water is imbalanced. The natural pH for pool water is supposed to be 7.4.

What Kind of Algae Is It?

Woman relaxing at pool with hat

There are three basic types of algae, which include green algae, yellow algae, and black algae. Green algae is the most common form that comes in a wide variety of colors and is typically found around the edges of a pool. If any area of your pool is heavily shaded, it’s possible that green algae will develop there. As for yellow algae, this is a strain of green algae that’s known to develop when the chlorine levels are low and the water temperature is warm. Even pools that are properly maintained can develop yellow algae.

When it comes to black algae, this form is usually found around the cracks and tiles of a pool surface. It’s also known to grow in areas of the pool that are shaded. If your pool has been outfitted with a vinyl lining, it’s highly unlikely that black algae will grow there. It’s a very thick substance, which means that it is resistant to standard levels of chlorine.

How to Treat Pool Algae

For pool algae to be properly treated, you will need to scrub the substance from the surface of your pool while running the pool filter. Once the pool has been aggressively brushed, it will need to be shocked, which is a simple process that involves adding chlorine to the pool water. You generally want to add three pounds of chlorine for every 10,000 gallons of water. This process typically needs to be completed several times before you can be confident that the algae has been completely eradicated. After the algae is gone, make sure that you add some Algaecide 60 to the water.

How Green Algae Is Specifically Treated

If you find that there’s a significant amount of green algae in your swimming pool, you can treat it by first analyzing the water in the pool to identify what the current pH levels are. The optimal pH level for a swimming pool is 7.4, which means that the water may need to be treated if the number falls below this level.

If you’re treating the pool with chlorine, it should be brushed extensively before being shocked. Your main goal should be to increase chlorine levels to above three PPM. A heavy amount of Algaecide 60 should also be added to the water, which will help to prevent the formation of green algae in the future. This process may need to be repeated a few times before you are able to get rid of the algae completely.

How Yellow Algae Is Specifically Treated

When you find yellow algae in your pool, it’s first important that you are able to determine that the algae is yellow as opposed to green. Green algae can be either blue-green or yellow-green in appearance. With yellow algae, the color can be yellow-green or even brown. The main issue with treating yellow algae is that it’s able to resist a certain amount of chlorine and can be hidden on filters and pool toys.

When attempting to get rid of the yellow algae in your pool, it’s important that you treat any items within the pool alongside the actual pool water. Make sure that you scrub every inch of the pool surface before shocking the water. It’s recommended that you add three pounds of chlorine for every 10,000 gallons of water. This treatment will likely need to be repeated up to five times in order to get rid of all algae in the pool.

How Black Algae Is Specifically Treated

The treatment for black algae is very similar to the treatment used for yellow algae. Once you’ve analyzed the water, it is essential that you brush the algae thoroughly, which is particularly important with black algae in order to break the slime layer. If you skip this step, the rest of the treatment won’t work as intended. As with yellow algae, you will likely need to heavily shock the pool water with chlorine if you want to eliminate the algae. High amounts of Algaecide 60 should be added to the water as well. This process should be repeated at least three times. Make sure that you brush the pool after each treatment.

How to Prevent Pool Algae

girl swimming in pool with inner tube

If you want to prevent the development of pool algae in the future, there are numerous steps that you should consider taking. The main prevention steps for pool algae include:

  • Make sure that you always have some kind of sanitizer in stock for your pool
  • Regularly inspect your circulation system to determine that it works properly and will continue to clean your water
  • Use algaecide whenever you treat your pool water
  • Shock the pool weekly with chlorine, which should keep bacteria and algae growth at bay
  • Consider using a vacuum when removing any debris from the pool
  • Make sure that you use a brush that won’t damage the walls of your pool
  • Create a brushing routine that will allow you efficiently remove the algae or bacteria from your pool

There are many great products that are available through water filtration companies to help you prevent algae or treat your pool water. At Sensorex, we offer extensive water sensors that can identify both the pH and chlorine levels in your pool. If the water is imbalanced, these sensors will provide you with precise readings that will allow you to determine if the water needs to be treated. The pH sensors available at Sensorex are varied and can accommodate many needs.

Using Sensorex Products to Identify, Treat, and Prevent Pool Algae

When you want to identify, treat, and prevent pool algae, the first step is to determine if your water is properly balanced. A great way to determine if algae is present in your pool is by identifying what the pH levels of your water are. If the levels are too high, it’s likely that algae could begin to grow. For basic monitoring, you should consider the pH1000 sensor, which is designed to be used with pools.

You could also use the FCL free chlorine sensor to determine if the chlorine levels in your pool are correct, which is important during the process of treating the water and getting rid of the algae. If you need some assistance with selecting the right products for your home pool, contact Sensorex today to speak with one of our representatives.

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Posted by Sensorex on January 14, 2020

Sensorex is a global leader in the design and manufacture of quality sensors for water quality and process applications. The company offers more than 2000 sensor packages for pH, ORP, conductivity, dissolved oxygen, free chlorine, chlorine dioxide, UV transmittance and other specialty measurements, as well as a full line of sensor accessories and transmitters. Its expert technical support engineers solve analytical sensor challenges with custom designs and off the shelf products.

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