How To Get Rid of Algae in a Saltwater Pool

How To Get Rid of Algae in a Saltwater Pool
How To Get Rid of Algae in a Saltwater Pool

How To Get Rid of Algae in a Saltwater Pool – Compared to a typical chlorinated pool, salt water pools are relatively simple to maintain. To prevent algae and other bacterial growths in your pool, these pools turn natural salt into chlorine. To keep these pools clean and clear, they typically only need a few chlorine tablets every now and then.

However, even saltwater swimming pools can turn green and slimy. You may have an outbreak if the water is left unattended for an extended period of time or if infected swimsuits introduce algal spores to your pool.

Why Is Your Saltwater Pool Filled With Algae?

The main causes of algae growth in swimming pools are either inadequate or missing sanitizing chemical treatments, such as chlorine, and possibly slightly elevated pH levels. High pH water is what algae consumes for breakfast, lunch, and dinner.

Additionally, you can see algae growth in your pool if the water is stagnant and inadequately sanitized. Because of this, it’s crucial to maintain pool water circulation with your filter and pump. When the water is flowing, algae have a difficult time growing.

Additionally, algae enjoys damp, gloomy areas with little water movement, such as:

  • Below your pool ladder
  • On the steps of your pool
  • Crease and crevices on every corner

Why did your sanitizer fail is the actual question.

The base chlorine level in a saltwater pool is lower than in a standard chlorine pool, despite the fact that your saltwater generator produces a steady flow of chlorine.

Saltwater pools are less abrasive to the skin and eyes because of this, but it also makes them slightly more susceptible to algae blooms.

You don’t have an algae issue all year because, under typical circumstances, the chlorine level in your saltwater pool is still high enough to combat the threat of algae.

But because conditions are subject to change, even a slight shift might give pool algae the upper hand.

For instance:

  • It’s possible to experience abnormally hot weather, which raises the temperature of your water and encourages the growth of algae.
  • You may have problems with your filter or pump, which results in inadequate filtration and circulation and encourages the growth of additional algae.
  • You can unintentionally allow your pH level to fall, which could stop your sanitizer from killing algae.
  • The list keeps on.

Whatever the cause, having algae doesn’t necessarily mean you’re a terrible pool owner; it only indicates that the water’s parameters have somewhat moved in favor of algae. Even the best of us experience it.

Algae Effect

Algae can have a number of negative impacts, including:

  • Releasing toxins into the water
  • Reducing dissolved oxygen levels
  • Lowering the pH of the water

Releasing Toxins

Algae can contaminate water by releasing toxins, especially blue-green algae or better known as cyanobacteria. According to the UN Environment Programme, algae produce toxins during blooming and release them when they die.

The toxins released by algae can cause various diseases such as nerve damage, liver damage, respiratory problems, skin irritation, and death in humans and animals.

Water that contains toxins from blooming algae usually looks different colors (green, blue, red, or brown), smells like rotting plants, and looks like foam or particles that fill the surface of the water.

Reducing Oxygen Levels

Oxygen levels are decreased as a result of water contamination brought on by blooming algae. Water-dwelling organisms need dissolved oxygen to breathe.

The National Oceanic and Atmospheric Administration reports that as algae disintegrate and die, they consume all the oxygen in the water, resulting in hypoxia. Hypoxia is an oxygen-depleted or low level in the water condition.

Lowering the pH of the water

Carbon dioxide is produced in large quantities by decomposing and dead algae, which reduces the pH (acidity) of the water.

Varieties of Algae and Lookalikes

Knowing the many types of algae and common algae impersonators is necessary before you can treat them properly. If you don’t handle it vigorously enough, you’ll have a rebound algae bloom in no time.

Green Algae

Green algae are the most prevalent type of algae seen in pools, and they reproduce quite rapidly. If your pool’s color changed seemingly overnight, it was probably the result of green algae contamination. In addition to producing energy, green algae eat sunlight. Because of this, algal contamination can swiftly spiral out of control on bright days.

Green algae frequently adheres to surfaces and has a slimy appearance. The good news is that even though green algae may spread quickly, it is the simplest to get rid of. You may likely need to shock your pool twice in order to clear your green one.

Mustard Algae or Yellow Algae

yellow algae
Mustard Algae or Yellow Algae

Mustard or yellow algae typically grow more slowly than green algae. In contrast to green algae, it thrives in calm water and gloomy areas. You might initially mistake it for dirt, pollen, or sand on the bottom or sides of your pool because it often has a dry or powdery appearance.

At first, a yellow algal infection could look like a smear or a blob. Overall, your pool does not have a pleasant appearance.

Yellow algae is harder to get rid of than green algae since it is resistant to chlorine. To completely control the yellow algal infestation in your pool, you might need to shock it three times.

Black Algae

Black Algae
Black Algae

Black algae might start as a few black patches that gradually develop into clumps and have a mold-like appearance. Black algae is less likely to infect pools with fiberglass or vinyl lining since it tends to grow more readily on porous surfaces. Do not swim in a pool that appears to be contaminated since black algae can make you sick.

Black algae are the most difficult to get rid of because they are more chlorine resistant than green or yellow algae. To stop the pollution, you might need to double shock your pool water.

Pink Slime

Pink slime is sometimes mistaken for algae, but it’s actually a bacteria. Pink slime, another issue that frequently affects swimming pools, is similar to algae. Pink slime can appear as streaks of goo or mucus. You should stay away from the pool until the contamination is under control because it is unhygienic.

Black algae and pink slime both have a strong will. To completely get rid of the bacteria, you might need to shock your pool three or four times.

Don’t Use Algicide To Kill Algae!

Putting too much algaecide in a pool is a mistake that many people make. Sometimes the required amount is miscalculated, and sometimes it is added at the incorrect moment.

A pool with too much algaecide will have water full of tiny, foaming algaecide bubbles, which can harm the filtration system. Additionally, too much algaecide might irritate the skin and eyes. Till the algaecide concentration goes down, it is advised to avoid the water.

Although it is a common and understandable response to the growth of algae in the pool, using a lot of pool algaecide is a mistake.

Algaecide is not the method to handle an algae attack; it is intended for routine treatment to avoid algae. Algae should be killed with pool shock, and algaecide should only be used to prevent new breakouts once chlorine levels have returned to normal.

Read: Water Bug Removal Instructions

How To Get Rid of Algae in a Saltwater Pool?

There is nothing particularly unique or remarkable about what we’re teaching here; getting rid of algae in a salt pool is pretty comparable to getting rid of algae in a conventional chlorine pool.

Having said that, this is still a sensitive process, and the fundamentals determine everything, therefore it’s crucial to adhere to these stages exactly.

1. Brush the pool

Brush the pool’s walls and floor before shocking it. You’ll see that algae grows and adheres to the walls and bottom of the pool. Clean your pool’s walls and floor as thoroughly as you can. It’s best if you can remove as much algae from the walls as you can.

After you’ve wiped off the top layers, chlorine will work better to treat any residue. Don’t forget to brush the difficult-to-reach spots behind the pool steps, ladders, and other obstructions.

2. Clean Up Any Loose Algae With A Vacuum

Vacuum your pool manually, going as thorough as you can. All of that floating algae detritus is just waiting to be vacuumed out. If at all possible, vacuum to waste to prevent returning the algae to your pool. After that, you might need to top off your pool with water to restore it to the proper level.

3. Water Testing and Balance

It’s VERY vital that you balance your chemistry before we treat the water, so the shock treatment can function as effectively as possible.

Since shock is really chlorine on steroids, chlorine always performs at its peak when the other components of your pool’s chemistry are stable. If you don’t do this, your shock therapy will lose its impact and you’ll be back where you started.

Of course, you’ll need to test the water to find any chemical imbalances before you perform any balancing. It’s also worth it if your kit doesn’t test for salinity.

This is also the time to restart your pump and filter system so that it can circulate any additional chemicals.

We probably don’t need to explain how to balance your water, but just in case, let’s give you a quick rundown.

A short reference for balancing a saltwater pool is provided below:

  • pH range: 7.2–7.6
  • Stabilizer (cyanuric acid) range: 70–80 ppm
  • Calcium hardness range: 200-400 ppm
  • Total alkalinity of 80 to 120 ppm
  • Salt content of 2700 to 4500 ppm (As this varies by model, check your salt cell manual.)

You’re ready for the enjoyable part once your pool has been washed, vacuumed, and all of your levels are within the ideal range.

4. Pool-Shock

To kill the algae, you will now shock or superchlorinate the water with a large amount of chlorine.

This procedure should already be familiar to you because it should be covered in your weekly or biweekly maintenance routine. By doing this, algae growth is stopped and chloramines and other heavy pollution are removed from the water.

In a saltwater pool, regular shocking is really one of the best preventative treatments against algae, but we’ll cover prevention in more detail later.

The crucial section is presented below:

Give the pool a double dosage of calcium hypochlorite shock if the water appears teal or light green as a result of the algae. A triple serving should be used if the water appears to be dark green, and a quadruple shock is recommended if it appears to be black.

Typically, 10,000 gallons of pool water can be treated with one pound of shock. For every 10,000 gallons, you will need two pounds for a double dose of shock, three pounds for a treble dose, and four pounds for a quadruple dose. Additionally, if the shock is administered to the water after sunset or at dusk, it will be more effective.

Then, turn on the pump and filter for at least eight hours so that the shock may circulate through the water and get rid of the algae. It is preferable to apply the treatment in the evening and let it operate all night because you must give the shock time without direct sunlight. The water in the pool should be a hazy blue color once the shock has been added.

Shock is used by pool owners to maintain the cleanliness of their water throughout the swimming season, therefore purchasing it in bulk can help pool owners save money. You’ll also have some on hand if you purchase it in quantity.

Note: To safely shock the algae in your salt water pool into oblivion without adding extra chemicals to the water, use calcium hypochlorite shock.

5. Start the filter

If the treatment was successful, your pool’s water should be significantly more cloudy and have lost the colored tint that algae had given it by the following morning.

A lot of dead algae should be floating around, and depending on how overcast it is outside, you might even notice clumps of dead algae at the bottom of your pool. If it is gray or white in color, it is dead.

At this point, you should run the filter 24 hours a day to keep the pool clear. Additionally, you might wish to add water clarifier to hasten the process. It is safe to enter the foggy pool, and the movement of the swimmers will help the filter remove the algae particles.

Repeat the method and shock the pool once more if the water color still seems teal or green.

6. Test and Balance the Water Again

Even after the shock treatment subsides, it will still be evident and may cause a small out-of-balance in the rest of your pool’s chemistry.

Calcium hypochlorite, a highly alkaline calcium-based shock, is the most often utilized kind of pool shock.

In other words, it will increase your pH and calcium levels in specifically, in addition to your sanitizer levels. Naturally, everything that increases pH also increases total alkalinity.

In other words, it’s crucial to test everything once more using a pool testing kit to see what has to be modified, regardless of how clean your water appears to be at this time.

This will strengthen your defenses against future algae blooms, especially if any traces of algae are still present after shocking, in addition to making the water safe for swimming.

7. Clean Your Filter

If everything went according to plan, your pool’s water should have now gone through your filtration system at least once.

As a result, in addition to the regular debris that filters must deal with, the filter will become clogged with all that dead algae.

While the clarity of your water should be almost back to normal, the filter will be blocked with all that dead algae and other detritus that a pool filter must cope with.

A blocked filter not only hinders circulation from functioning properly but also has the ability to reintroduce algal spores into the water.

Consequently, it is a good time to clean or maybe replace your filter.

Depending on how severely affected your DE or sand filter is, you can either backwash it or replace the filter media.

Even if you have a cartridge filter, you probably won’t be able to completely remove all of the algae by merely hosing it down. Instead, soak it for several hours in a filter cleaning solution before hosing it down, or simply replace the entire unit.

8. Disinfect Your Tools

Any equipment you used during this process needs to be completely cleaned and sterilized before being used again because algae can survive outdoors for weeks or even months.

This includes any toys or floats you took from the water before shocking, as well as cleaning tools like brushes, skimmer nets, or vacuums.

How to Prevent Saltwater Algae?

It’s been said that prevention is better than cure: an ounce is worth a pound. This is applicable to pool maintenance even though it is typically used to describe medical issues.

In order to prevent a full-blown algal contamination, keep your pool clean and balanced. You have entered potentially hazardous terrain if your pool water starts to turn foggy or you notice colorful spots in the water. Immediately treat your water.

You can also take the following actions to stop algae growth in your saltwater pool:

  • Get a pool cover, but be aware that, depending on the style you have, salt water may cause damage to certain elements of the cover.
  • Get a smart water monitor to handle the testing for you or test your pool’s water every day.
  • Don’t rely on your water filter alone to keep the pool clean. Before it gets out of control, you can proactively vacuum your pool to remove any potential buildup.

Read: How to Eliminate the Effects of Weed on Your Eyes


Is it safe to swim in an algae-infested pool?

Yes, technically, but it’s not advised. Although swimming in pools with a lot of algae is not detrimental to swimmers, such pools may contain dangerous bacteria and pathogens like E-coli. Additionally, hazy water brought on by algae might be dangerous if swimmers are unable to see the pool’s bottom. Avoid swimming in unclean or improperly sanitized pools.

Does phosphate remover eliminate algae in swimming pools?

Phosphate removers work by cutting algae off from the food source that makes them grow. The more phosphates there are in the water, the more algae may eat. However, phosphate removers won’t fix any underlying problems with the chemistry of the water, such as low chlorine or unbalanced pH levels. You won’t require a phosphate remover if you maintain your water sterilized with chlorine, algaecide, and the odd pool shock.

Does shock kill the algae in pools?

Yes, the main component in eliminating algae in swimming pools is shock. Shock increases the amount of free chlorine in your pool’s water to the point where algae and other impurities start to die off. You may need to add 2-4 doses of shock, depending on how severe your algae growth is. Additionally, it is typical to observe hazy water after shocking algae to death. After you run your filter, the water should become clear. Prior to utilizing shock, make sure to vacuum and brush your pool. Large amounts of algae are removed and made loose by doing this.

Last Words

Once you understand the causes of pool algae growth and how to avoid it, you shouldn’t have to deal with another severe contamination ever again. But you need keep in mind that prevention is always preferable to cure, therefore Pounds are equal to an ounce.

Once the algae has been entirely removed and the pH balance of your pool has been restored, your pool is ready for use. Try to avoid swimming in pools with algae or slime buildup because some varieties can make you sick, even though the majority of algae are not harmful.

Check other usefull article here

Leave a Comment