16230 West Bellfort
Sugar Land, TX 77498


9201 FM 1488 #150
Magnolia, TX 77354

How to Get Rid of Black Algae in Swimming Pools

If there’s one thing you don’t want to see when you look in your pool, it’s black algae. While green algae can be problematic, black algae is something entirely different. Not only is it difficult to get rid of, but it also makes your pool difficult to swim in.

What causes black algae in a pool? What do I do about black algae in a saltwater pool? How do I get rid of black algae in my pool fast? Here are some answers for you.

What Is Black Algae?

Algae is a plant. It grows all over the world. There are many types, from single-celled algae to seaweed. Black algae is not the same as green algae. While green algae is a plant, black algae is a bacterium. It is blue-green, but it gets its black color from pigments. Black algae is dangerous. It is full of cyanotoxins, which are natural poisons. If you swim in water that has it, or you drink it, you can get sick. The same is true for any animal that drinks or swims in the water. Signs of sickness include nausea, severe cramping, and vomiting. If the illness becomes severe enough, it could lead to liver damage.

What Does Black Algae Look Like?

Black algae gets into your pool from outside water sources. You may introduce it into your pool through a water hose. People may also have it on their swimsuits when they enter the water. When an infestation starts, it looks like small black or blue-green dots. It can also look like clumps of black or blue-green mold. Instead of floating freely in the water, the algae clings to areas close to the surface of the water. This is especially true in rougher pool surfaces, such as an edge. If the area has black algae, you may be able to scrape it off with your fingernail. However, it is extremely hard to remove. It will not come off with a pool brush. It may not come off even with an algae brush.

How Can I Get Rid of Black Algae?

While green algae is fairly easy to get rid of, black algae is not. It doesn’t matter whether it’s a chlorine pool or a saltwater pool. The first thing you must do is clean the pool’s filter. If it seems like there’s a lot in your filter, you will need to use filter cleaners.

Are you worried that you may not have gotten all the algae? You need to replace the filter cartridge or filter medium. That way, you will be sure there is no algae in the new filter.

After you clean the filter, your next step is to test the water. You will need to figure out what your pH levels are, so you know what kind of chemicals to use. Then, you will have to thoroughly scrub every inch of your pool with a stainless-steel bristle brush. After you have brushed all of the algae off the surfaces, you need to shock the pool. This will kill the bacteria.

Once you have shocked the pool, you will need to double-check the entire pool for any signs of it. Make sure that each time you scrub, you wear protective eyewear and gloves. If there are stubborn spots, you will need to use chlorine directly on them. After you have finished scrubbing, make sure you use chemicals to discourage algae growth. Then, let the pool rest for 24 hours to make sure there is nothing left of the black algae menace.

The team at Precision Pools and Spas is always happy to provide pool owners with the helpful information necessary to take care of pools properly and keep them sparkling. We are a Texas Premier Pool Builder. Please feel free to contact Precision Pools & Spas at any time.

Precision Pools & Spas
2 Convenient Locations
16230 West Bellfort, Sugar Land, TX 77498
9201 FM 1488 Suite 150, Magnolia, TX 77354
Phone: 281-990-6945
Email: [email protected]

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