A green pool or strange yellow or black spots on the walls can make you want to stay out of the water. The good news is that most pool algae can be treated.

If you’re wondering how to get rid of algae in pool water, start by figuring out which type you have. Green, mustard, and black algae look different and may need different treatments.

Algae is more likely to grow when chlorine levels drop, water isn’t circulating well, or debris gets into the pool. Heavy rain and wind can also throw off your pool chemistry.

Here’s how to spot the type of algae in your pool and get rid of it.

Green Algae in Pool

Green algae is the most common type of pool algae. It can make the water look cloudy or turn the entire pool green. You may also notice a slippery green coating on the walls, steps, or floor.

Green algae often shows up when chlorine is too low or the pool isn’t circulating and filtering water properly. It’s usually easier to remove than mustard or black algae.

Start by testing and balancing the water. Brush the walls, steps, and floor to loosen the algae, then shock the pool with chlorine according to the product directions. Run the filtration system and vacuum up dead algae.

Clean or backwash the filter as needed and test the water again before swimming. A pool with a lot of algae may need another round of treatment.

Black Algae in Pool

Black algae usually looks like small black or dark blue-green spots on the walls or floor. It’s most common on porous pool surfaces such as plaster and concrete.

Black algae can work its way into tiny pores in these surfaces and develop a protective outer layer. That’s why simply wiping away the spots may not solve the problem.

Scrub the affected areas thoroughly with a brush that’s safe for your pool surface. This breaks through the outer layer so chlorine can reach what’s underneath.

Then test and balance the water, shock the pool, and run the filtration system. Clean the filter as needed. You may need to brush and treat the affected areas more than once because black algae can be stubborn.

Mustard Algae in Pool

Mustard algae, also called yellow algae, usually looks like yellow, tan, or light brown dust. It often appears on pool walls, steps, and areas that don’t get much sunlight.

It’s easy to mistake mustard algae for dirt or pollen. But unlike dirt, it tends to cling to pool surfaces and come back after you brush it away.

Mustard algae can also stick to swimsuits, toys, brushes, and other pool equipment. If you don’t clean those items, you can bring the algae right back into the water.

Brush and vacuum the pool thoroughly, then test and balance the water before shocking the pool. Run the filtration system and clean the filter as needed. Clean anything else that’s been in the pool, including toys and equipment.

You may need to repeat the treatment or use a product made specifically for yellow or mustard algae.

How to Get Rid of Algae in Pool and Keep It From Coming Back

Once your water is clear, regular maintenance can keep algae from returning. Test your water regularly, keep chlorine and pH at the proper levels, and make sure your filtration system is working well. Regular brushing, vacuuming and filter cleaning also make it harder for algae to take hold.

You can do all of that yourself. But algae cleanup can mean a lot of testing, brushing, vacuuming, and follow-up treatments.

Or skip the scrubbing and let us handle it every week!

Our pool cleaning and maintenance services keep your water clean without adding another chore to your list. If you’re in the Fort Worth area, call 817-389-2688 for a free quote.

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