Algae in your Pool: How to get rid of it (without a Vacuum and Chemicals) - Sutro, Inc

Algae in your Pool: How to get rid of it (without a Vacuum and Chemicals)

Let’s imagine the best summer day you can think of.

The sun is shining, the drink in your hand helps you mitigate the thirst you feel, and the suffocating hot temperatures are inviting you to refresh yourself in the swimming pool you’re so proud of. So, you begin to walk, slowly, towards the pool, feeling the cold water in your mind.

But then, you suddenly see it. The clear water you expected isn’t there. In its place, green coloured algae are populating your pool without even asking for permission. 

How can this be possible? Well, the fact is that algae can grow up in any pool. Typically, it happens after someone goes to the pool wearing the same suit he used in a lake, river… But, of course, this is not the only cause.

How can we get rid of this guest? Can you get rid of algae in the pool? Yes, we do. But we should first know the various algae types we can encounter.

Let’s dive in!

  1. What Are The Different Types Of Pool Algae?
  2. What Causes Pool Algae?
  3. Dangers of Pool Algae
  4. How to Kill and Get Rid of Algae In Your Pool FAST?
  5. How to remove algae from a pool without a vacuum?
  6. How to get rid of algae in a pool without chemicals?
  7. How to get rid of algae in above ground pools?
  8. Can You Use Algaecide to Get Rid of Pool Algae?
  9. Can You Use Pool Flocculant to Remove Pool Algae?
  10. Does chlorine kill algae?
  11. Does phosphate remover kill algae in pools?
  12. How long will it take to clear the pool?
  13. Tips to preventing and stopping pool algae from coming back
  14. Green pool water and pool algae during winter

What Are The Different Types Of Pool Algae?

Algae are often classified for their color, which is the easiest characteristic to see. Different kinds of algae mean other processes to clean the pool, so it’s essential to know which is the one that is invading your water.

Check which one you have, and see description below:

🦠 Type of Algae 📝 Description
Yellow Algae Also known as Brown or Mustard Algae, it’s usually confused with pollen or sand. Is it mustard algae or pollen? It’s easy to find it out: Mustard algae sticks to the walls while pollen floats. It’s most probably found in southern climates and resistant to some chemicals such as chlorine. Yellow algae attach themselves to objects and tools. Even the pool filter can be a nice home. It can be difficult to get rid of it if you don’t properly clean the tools and suits used in the water.
Green Algae The most common one and also the most known. At least, it is the easiest to get rid of. It commonly makes the pool’s water cloudy, sticking to the walls and floors and giving a non-desirable green color to the pool.
Black Algae Well, to be fair, this isn’t an alga. It’s commonly known as black algae, but, in fact, it’s a cyanobacterium. And this is not good news. It sticks to concrete, rooting inside and making it extremely difficult actually to kill it. If you don’t kill every single root of it, it will grow back quickly. It does not float, just grows on the floor, walls, and textured surfaces


Once you determine what kind of algae is populating your pool, it’s time to go and free your water from these undesirable invaders!

What Causes Pool Algae? 

Usually, the algae can appear due to some poor filtration or poor water circulation. This can be caused by a small filter or even problems in the pump system. Dead spots can appear if the water does not circulate evenly and cause algae growth.

Also, not having good maintenance, like low chlorine levels or an imbalanced pH, are common issues that can cause algae problems. 

Dangers of Pool Algae

First of all: Green algae isn’t dangerous by itself for your health. But, we can’t say the same about the bacteria living in it. Green algae usually harbor bacteria that can cause skin infections.

Also, that water could be ingested (accidentally), which is something usual when kids play. That could cause fever, diarrhea, and all symptoms associated with an infection. Same for eye infections.

This is the same for other kinds of algae, black and mustard. Bacteria like E.Coli can live in them, as well as some mosquitoes, etc.

Also, the algae can make pools floor slippery and water cloudy. Obviously, that can be a danger for more physical harm. Bumps, cuts, and other injuries can be caused by suboptimal conditions for swimming or playing games in the pool.

How to Kill and Get Rid of Algae In Your Pool FAST?

What is the best way to get rid of algae in the pool?

Step by step, you should proceed like this:

  • First, we must manually brush and vacuum all the algae found on the walls and floor. Just remove as much as you can. Brushing it strongly not only helps release the algae but also helps chemicals doing a better job killing all algae that cannot be removed.

  • Second, all tools, swimsuits, and everything that has been in contact with the water must be cleaned with a bleach dilution. One part of bleach for ten of water is the way to go for not damaging them, while it is enough to eliminate all bacteria and algae that could be stuck to it.

  • Now, you should test your water. It’s crucial to balance your water so the shock treatment doesn’t lose its power. For example, a bad PH can mitigate the strength of the chemicals used, so be sure to balance all parameters.

  • The most important step: It’s time to shock the pool. The amount of shock depends on the algae you’re trying to kill.
  • What color are dead algae in a pool? Actually, it’s a cloudy blue-like color. And this is the color you should expect to see now. The shock treatment should have killed all the algae, and that color is the best indicator.

    Just run your filter constantly to remove the dead algae from the water. You can use a clarifier to do it faster or a flocculant so all drops to the floor and can be vacuumed. Of course, when this process is over, you should clean the filter.


How to remove algae from a pool without a vacuum?

What if I don’t have a vacuum? How can I kill algae? I can’t get rid of algae in the pool, isn’t it?

First of all, you can use a sieve or a pool net as a substitute. It’s not the same, but it works.

Another possibility is letting your filter clean all the water. Still, you should be aware of cleaning the filter due to the amount of algae collected. Also, check the pump so it doesn’t get obstructed.

How to get rid of algae in a pool without chemicals?

You can get rid of all the algae without using any chemical, just by brushing, filtering, and using the vacuum. But, the fact is, it’s going to come back soon. Maintaining the balance in the pool and killing the algae is really important.

Chlorine prevents microorganisms from growing. So yes, you can kick algae out of your pool. But it will be back in days or weeks.

How to get rid of algae in above ground pools?

Actually, it’s no different. You can follow the same steps. Even if the pool is small, it can be a great idea to change the water.

Obviously, that doesn’t mean you don’t have to kill the algae in the walls and floor after adding the new water. Same about the filters, tools, etc.

Can You Use Algaecide to Get Rid of Pool Algae?

Algaecide comes in different forms and compositions, and each one is better for a different kind of algae.

It helps kill algae, especially black and mustard algae, which are more resistant to chlorine. But by itself, it isn’t as helpful as chlorine for getting rid of algae in your pool.

Can You Use Pool Flocculant to Remove Pool Algae?

As said before, the flocculant is an excellent help to remove the algae, only when it is already dead. It will make dead algae fall to the ground, so it can be removed with a vacuum.

Does chlorine kill algae?

Actually, it is the most effective chemical for killing algae. Shocking the pool can just be made by using a chlorine shock. Black algae are more resistant to chlorine, but they can also be used for it in enough quantities.

Does phosphate remover kill algae in pools?

Phosphate is a primary source of food and nutrients for algae. So removing it will always be a nice help, especially for prevention. But it will be difficult to kill algae only using a phosphate remover, especially with black algae.

Phosphate removers can be handy for, as said before, preventing algae growth. Even the phosphate can affect the chlorine levels, so if your pool demands too much chlorine, a phosphate remover can be the way to go.


How long will it take to clear the pool?

It primarily depends on the size of the pool. Also, algae growth level and type. For example, black algae require much more effort to get rid of it than green algae. Also, pool construction material can lead to a huge difference.

A nice estimation for a full grown algae pool can be one to three days for a fiberglass or vinyl pool, while a concrete pool can take a week. But as said, it would depend on the pool’s size and amount of algae.

Tips to preventing and stopping pool algae from coming back

The first step should be maintaining the water balance, especially regarding chlorine levels. Good chlorine levels can stop all algae from growing in your pool, so it’s the primary parameter to look at.

Another good preventing step can be using a good phosphate remover if you have problems with algae continuing to re-grow after cleaning the pool. The same can go for algaecide, which can help prevent the worst cases of algae from reappearing.

Green pool water and pool algae during winter

In winter, most pools tend to grow green algae due to its lack of prevention and maintenance. A dose of algaecide can prevent it, so it can be a nice inversion if we don’t want to have to clean completely grown algae when the summer comes.

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