How to Remove Black Algae from Your Pool

Keeping algae out of your water is half the battle when it comes to owning a swimming pool. The majority of swimming pool chemicals are designed with this sole purpose in mind, keeping your water clear and safe for everyone. 

The worst-case scenario for any pool is the build-up of black algae. While rare and avoidable with good maintenance, if it does happen, you need to act fast and effectively.

If you require any equipment such as a swimming pool cover to help support your swimming pool chemicals, you can check out our range of supplies instore and online. Swimming pool covers are especially useful as they ensure that the swimming pool chemicals target bacteria and algae, as opposed to large organic matter such as leaves or debris, meaning fewer chemicals a needed for the water to remain balanced.

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What is Black Algae?

 

When we think of algae, we usually think of green water. In fact, algae is just a term referring to certain types of plants that can grow in water, meaning there are many variations.

The most common type of algae is green and is known for being fast-moving and equally fast-growing. However, there are also yellow and red/pink forms.

At the highest end of the scale is black algae, named after its colour. It’s scientifically known as cyanobacteria and is by far the toughest and most dangerous form of algae. It is commonly found in rivers, seas and other natural water sources and has an appearance similar to mould.

Black algae are incredibly hard to deal with, as they have natural shields that protect it from chemicals such as chlorine. If you have a significant build-up, the process of getting rid of black algae can be a long and arduous one.

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Why is Black Algae Dangerous?

 

As the name suggests, black algae are actually a form of bacteria.

The reason why black algae are potentially dangerous is that it produces toxins which then make their way into the water. While unlikely to cause serious ill-health, pools with black algae have the potential to make swimmers and other animals sick.

How To Tell If My Pool Has Black Algae

 

As mentioned above, black algae actually have more similarities to mould in terms of appearance. Given the work that needs to be done removing black algae, you want to make sure you’re looking at the right thing!

Beyond its colour, here are some other tell-tale signs to watch out for:

  • - The location – black algae usually form on rough surfaces, such as plaster or cracks.
  • - It will often appear as small dots or clumps.
  • - Black mould can be seen floating in the water, although it will be dead in this state.
  • - Unlike pool stains, black mould can be scraped off, although it is challenging.

How to Get Rid of Black Algae

 

The process of removing black algae from your pool is a long and difficult one. How badly your pool is affected will change how rigorous you need to be, but generally, all methods follow this pattern.

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Clean Your Filter

If black algae live in your pool, there’s a chance they live in your filter. If you only have a small amount, you may get away with a simple backwash. However, if there’s a lot of black algae, you might want to replace your filter media entirely to make sure there’s no return.

Brush Your Pool

Chemicals are not as effective against ingrained black algae, so you need to do a bit of old-fashioned manual labour to help them out.

The key here is to be as thorough as possible. A rigid wire brush is recommended to really dig out the algae; you should go over the whole pool, in case there is a little outbreak that isn’t noticeable just yet.

Chlorine Shock

Once the algae’s been dislodged, your chlorine has more of a chance. As with any outbreak, the next step is to shock your pool to destroy any algae that’s alive in the water.

Some people recommend doing as much as quadruple the regular shocking dose for removing black algae. We recommend speaking to a professional, such as our team at 1st Direct Pools, about your pool and issue first.

When performing the chlorine shock, consider allowing your cleaning utensils to sit in the water so there’s reduced risk of black algae surviving on your tools, which could then re-enter the water.

Repeat

Often, people find that the above isn’t enough to rid their pool of black algae altogether. You will likely need to brush the pool again and potentially re-shock it to eliminate any threat of black algae re-emerging.

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Preventing Black Algae from Returning

 

After you’ve dealt with your outbreak, you’ll want to ensure it doesn’t return! As mentioned above, make sure you thoroughly clean all tools used during the cleaning process to ensure there’s nothing left surviving there.

Black algae are rare, and one of the main ways it gets into pools is through uncleanliness, particularly by people visiting natural water sources. For example, if someone went swimming in the sea or a lake and then went into your pool without properly cleaning their equipment, this could cause a spread.

The best way to stop black algae from appearing in your pool, therefore, is simply to maintain the cleanliness of people and equipment. That, combined with good pool management in terms of chemicals like sanitisers and pool algaecide, should stop black algae from taking over your water.

Hopefully, this guide will help you conquer your black algae problem for good! If you need any advice specific to your situation, feel free to give our helpful team a call.