Does It Matter What Types of Swimming Pool Algae You Have

If you are a pool owner then sooner or later you are going to have a chemical problem with your pol’s water especially when the summer’s weather changes from warm to hot and the pool’s occupants go your kids to their friends and few pool parties then you wake up one Monday morning with algae in your pool. Does it matter what type of swimming pool algae you have?

No, Green, Yellow & Black are all treated the same

Balance H2O Chemistry
Scrub & brush pool’s walls and floor
Run filter 24 hrs.
Super-chlorinate to 8ppm+
Use an algaecide 2-3 days after shocking
Use a Flocculant
Vacumn to waste
Increase Maintenance
Bump chlorine residual in between your shocking schedule

Algae will find a way to survive in your swimming pool no matter what the residual is especially in spots where they can hide like cracks or crevices where colones can set up and make a home and as soon the pool water is to their liking can explode and populate.

 Understanding Algae Infestation in Your Pool Water


The word ‘algae’ may bring to mind a singular image or concept, but there’s more to it. Actually, there are several different types of algae that can bloom or create a slimy mess in your swimming pool. Some common types include green algae, black algae, and yellow algae, each with its unique features and impacts on your pool surfaces and water.

Green algae are the most common type of pool algae. It can spread rapidly, turning pool water into green, murky slime. When we’re talking about green algae, it’s important to pay attention to your filters. You’ll notice that low chlorine levels often accompany this form of swimming pool algae. As such, its prevention revolves around maintaining chlorine levels of 1-3 ppm or parts per million in the water.

On the other hand, black algae pose the greatest challenge to pool owners. Unlike green algae, black algae firmly attach to the pool surfaces, making it harder to get rid of them even with vigorous brushing. Maintaining a clean filter and having powerful pool pumps can assist in its prevention. If it manages to establish itself in your swimming pool, stronger chemicals or special cleaners may be necessary.

Yellow algae are less common, but they’re not less troublesome. They are usually found in parts of the pool that do not get much sunlight or have stagnant water. Shocking the pool with high levels of chlorine can rid the pool of yellow algae, but like black algae, you might need specific chemicals to deal with it effectively.

Treatment and maintenance strategies for each are the same. For green algae, you can manually vacuum and scrub the pool, run the filter continuously until the water clears, and maintain the chlorine levels.

The approach to dealing with black algae includes brushing the pool (preferably with a stainless-steel brush), shocking the pool water with high doses of chlorine and algaecide, and running the filter pump to remove dead algae. For yellow algae, routine shocking with chlorine and thorough brushing should be combined with algaecide treatment and periodic filter cleaning.

The best course of action for all algae involves regular pool maintenance, such as keeping your pool’s pH level between 7.2 and 7.8, ensuring your filter is in good condition, and testing chlorine and salt levels regularly.


Strategies for Combating Different Types of Pool Algae in Your Hot Tub


The type of algae found in your pool or hot tub can determine your approach to maintenance and cleaning. It’s more than just the swimming pool’s aesthetics that are affected it can damage your pool equipment

Algae can significantly impact the parts of your pool system, like the heater, filter, and spa heaters. Understanding the type of swimming pool algae you’re dealing with is thus crucial, as not all types can be effectively fought with a simple algaecide treatment.

Green algae is the most common type of algae found in swimming pools. This type of algae finds it easy to open shop on a pool surface, particularly when chlorine levels are low. You can usually find green algae floating freely in the pool, but it can also cling to the pool surface.

To get rid of green algae, your algaecide of choice should contain a mix of chlorine and a good type of broad-spectrum algaecide. Pool owners must also make sure to balance the level of chlorine in the pool as part of routine pool maintenance.

The black algae, however, is the toughest to handle and invades swimming pools and hot tubs differently than green algae. Black algae usually appear as small black spots on the pool surface but tend to extend roots into the pool’s plaster, which makes it very difficult to completely eliminate. Regular pool cleaning tools alongside algaecides formulated to combat black algae are particularly useful here.

Cleanliness is paramount in avoiding any form of pool algae in your hot tub. Regular upkeep in terms of scrubbing, filtering, and balancing the chemicals in your pool goes a long way. While your pool filter helps remove physical debris from the water, heater spare parts maintenance ensures the continued performance of your pool’s heating system. Every pool owner has a unique spa view toward pool maintenance, but one thing remains consistent the need to keep your pool clean and safe.

Regular maintenance on your pool is very important. It keeps your pool looking good, extends the lifespan of your pool’s installation like pool surface, spa heaters, and filters, and ensures the continued enjoyment of your private retreat. A balanced pool and Chlorine will kill any kind of algae regardless of the color, some more stubborn ones need more treatment. Prevention is the best treatment.

Common Types of Green Algae in Pool Water


 Common Green Pool Algae

Coccoid green alga. Unicellular Green Alga, 100X at 35mm. Very common... | Microscopic photography, Biology art, Green algae
Unicellular Green Alga, 100X

The most common and easily recognized of the main types of algae are green algae. Recognizable by its bright green color, this type develops in three stages: teal, dark, and black green. No matter the stage, this algae spreads fast and will coat a pool in a slimy, slick film. Luckily, green pool algae are the most common in pool water and the easiest variety to kill because their the easiest to spot.

The higher temperatures and Bather loading during these summer months can bring inconsistency in a pool’s sanitizer levels, and algae can rear its ugly head. Algae is a single-celled plant form. It uses the process of photosynthesis to manufacture its own food. It comes in a very wide variety of colors and forms, making it adaptable to almost any condition.

Due to algae’s microscopic size, it takes literally millions of these plants to accumulate to be noticed by the naked eye! By that time it may be too late and very costly to correct.  As we tell all our customers: The best way to do away with any kind of algae is through prevention!  Green algae can grow to the wall ladders or float in the water. Get rid of it by brushing the pool, shocking, and adding Algaecide 60 to a schedule especially in the summer whether you need it or not.

Yellow Pool Algae (Mustard Algae)


Yellow Pool Algae

Those bright spots gathered around the walls of your pool are yellow, or mustard, algae. This type of algae is rare, typically only appearing in humid climates and sticking to shadier corners and edges of your pool. This algae lacks a certain pigment, which causes them to appear lighter in color. But they are still Algae. 

They usually form in small colonies of only a few cells. Yellow algae grow slower than the others but being somewhat chlorine resistant, it is difficult to get rid of, and it may take multiple attempts to fully rid it from your pool.

A close relative to green algae, mustard algae can be yellowish, yellow-green, or brown in color and is typically slimy. Commonly mistaken for dirt or sand, mustard algae will persistently cling to pool surfaces, light fixtures, wall fittings, ladders, and other items, like toys floating in the pool or bathing suits.

Mustard algae is typically found in warmer regions, but it can grow in any pool or spa. Unfortunately, mustard algae is common and without proper water care, any pool or spa surface can be a home to it.

Since mustard algae is chlorine resistant, it can be more resilient to get rid of once it finds a home in your pool or spa. It is important to address mustard algae immediately because it can quickly transfer from pool surfaces to toys, floats, and bathing suits. While mustard algae can be brushed or knocked off, you’ll want to treat it correctly to ensure it doesn’t come back.



Black Pool Algae (Blue-Green Algae) Growth on Walls


Black Pool Algae

Lastly, the third type of pool algae is black, a breeding ground for harmful bacteria. As the very worst type of pool algae, black algae has the ability to seep into the concrete and cause structural damage to your pool if left untreated for a long period. Growth of black forms of algae on Surfaces varieties of algae types on pool surfaces.

When you see pools that have been let go for long periods of time that’s when you’ll see black algae spots on the surface of the pool structure (walls and floor) the liner or concrete. It will begin as black dots scattered across the pool floor and pool corners before spreading rapidly across the rest of the pool. But they are still Algae.

Blue or green algae is the most common type of pool algae, but it is no less difficult to clean. Green algae cling to the walls of your pool, but can also be free-floating which creates a murky, swamp-like film over the pool water. You guessed it you’ll need the good ole’ long handle pool brush and some borax.

In the same way that baking soda can be a spot treatment for black algae, household borax does the same for blue and green algae. Simply use the borax to scrub away algae that are sticking to your pool walls and floor, then use the brush to knock it off. Follow up by vacuuming up the rest. You will have a much easier time once the borax has stopped the algae from growing.

If you encounter black algae, you’d better roll up your sleeves because you have some scrubbing to do. Grab a brush and some baking soda. Bicarbonate, is the active ingredient in baking soda, is an effective spot treatment to help kill the algae and loosen it from the wall.

Make sure you really get every last particle free; black algae has particularly long and stubborn roots which makes it a stubborn strand. With enough scrubbing, you can rid the black algae for good.

In the end, all types of Pool Algae are plant life, regardless of their color. Balance your Pool Water Use an Algaecide and Shock your pool water weekly to kill this microscopic plant life before they get going.


What is the Best Swimming Pool Return Jets Position?

At the Deepest End of the pool
turn the Return Jets (eyeballs) located on the pool walls angled down toward the bottom of the pool at a 45° angle

In the Shallow End of the pool
turn Return Jets clockwise to about 8 o’clock at a 45° angle so the return water to the pool is mixing …………………………………………………………………. Read more



How to Keep Algae Out of Your Swimming Pool > Pool Pal pool algae clean


What Happens When You Pee in the Pool?

  • Pee contains uric acid
  • It comes in contact with Free Chlorine in Pools
  • Reacts forming Chloramines & harmful disinfection by-products
  • like Trichloramine & Cyanogen chloride
  • Studies say Up to 8-20 gal. of urine in Public pools
  • 2-3 gals. in backyard pools, according to a study by the University of Alberta .……………………………………………………………………… Read more

Treatment for Common Pool Algae for Pools


Using calcium hypochlorite shock, or cal-hypo shock, is an effective algae treatment. Follow the package instructions to determine the dose for your pool size, then multiply that by two, three, or four depending on which type of algae is in the swimming pool.

For an isolated algae bloom, use granular chlorine to treat it. You can also get a brush, apply algaecide to the water, and scrub. If you have free-floating algae, you’ll have to shock your pool. To start, before shocking balance your pool water to get your pH between 7.1 and 7.3. 

Use a pool brush to vigorously scrub any pool surfaces covered in algae, including the walls, floors, and steps. Apply a green algaecide according to the directions on the label. Let the water circulate for 24 hours, then brush the pool surfaces again. Vacuum or backwash to remove any remaining dead algae.

You’ll always have algae in your pool, but a few things can kick off an algae bloom. You could have inadequate filtration for your pool’s size or low or inconsistent chlorine levels. Bad water circulation with dead spots or pool imbalance in your pool chemicals is also two big culprits.


The treatment for Green-Yellow-Black Algae:

  • Balance your pool’s Chemistry
  • Scrub and brush the walls and floor of the pool
  • Run your pool filter 24 hours a day for the next few days.
  • Super-chlorinate(make sure the FC levels are over 8ppm or above
  • Use an algaecide days after you shock your pool.
  • Use a Flocculant to settle out debris
  • Vacumn the pool bottom to waste on the filter
  • Whatever your Maintenance Schedule was increase it during these “dog days of summer”
  • Bump your chlorine residual in between your shocking schedule, especially in the late summer



What are the Red Cross Temperature Guidelines for Swimming Pools?

According to the Red Cross

  • Pool temperatures for infants-90°-93°F
  • pre-school-aged children-90°-93°F
  • Seniors should be-90°-93°F
  • Pools used for physical therapy must also be at a higher temperature, ideally around 86°F.
  • For exercise or competitive swimming-77°-82°F
  • As a general rule, keep it about 77°-84°F …………………………………………………………………………………………………………… Read more


JimGalloway Author/Editor


Recent Posts