How To Get Rid Of Algae In Pool



Algae is a common word known to almost every pool owner. Algae, an aquatic organism contain chlorophyll and catalyses, when comes in contact with sunlight, photosynthesis the growth of this algae in water.

There are different factors that lead to growth of algae in your pool. It might be in-appropriate use of chemicals, carbon dioxide present in water, excessive exposure to sunlight or poor filtration of pool.

There are 4 major types of algae present in swimming pools irrespective of the fact whether they are in ground or over ground pools

  • Green Algae
  • Yellow Algae
  • Pink Algae
  • Black Algae

Out of these four algae, the most common is the green algae which affect your swimming pool the most. So, if you want to know different ways to get rid of green algae, read along. 

Steps to get rid of algae

Brushing the pool

This is the simplest of all the methods to get rid of algae from in-ground pools and above-ground pools.

Special attention should be paid to nooks and corners or behind the pool stairs, where the algae growth is maximum.

Be enthusiastic and brush wholeheartedly to eliminate the algae as much as possible by this easy method.

You can make this a family activity involving your kids to participate. I am sure they will amaze you with their energetic contribution. 

“Always use a brush that is compatible to the pool-type. Nylon brush for vinyl-coated pools and steel brushes for concrete tools are recommended”

Chlorine shock

Green water pools may look good and fascinating, but only the natural-pools not the in ground pools or the above ground pools.

Green water is a clear indication of algae in pool. As soon as you see such a condition, treat the pool with high quantity of chlorine.

This is also called shocking because of sudden treatment of the pool with high amounts of chlorine.

This is an effective measure but may take a few days (up to 5 days), depending upon the extent of deterioration of pool due to algae.

Optimize the PH level

Growth of Algae directly depends upon the pH level of water. Algae will start growing if the pH level of water is not in the desired range of 7.4 to 7.6. Algae will breed if pH level is between 6.5 and 12.5.

 Optimum pH level of water lets the chlorine present in water to work effectively thus maintaining the overall fitness of pool.

Sanitization of pool

Regular Sanitation of pool keeps the algae away from pool.  The pools must be treated with trichlor, which is considered an effective sanitizer but beware of using it in vinyl-pools since this chemical can bleach the walls and floor.

You can also use liquid chlorine. Another point to take care is that you should always sanitize the pool in evenings since UV rays from sun diminish the effect of sanitizer.

Once the pool is shocked with sanitizer, it is essential to circulate the water for at least 3 days.

Vacuum the residual algae.

Once the live algae are destroyed, it is time to rub off the dead algae, which can be done by manual vacuum machine.

 The other way to get rid of residual algae is by using the installed filter system, which may take few days to achieve 100% algae-free pool.  

Adding a flocculent will ease the work of vacuum since flocculent will clot all the algae together and will be easy to filter out.


“Flocculent treatment should be followed by chlorine shock treatment before using the pool, to achieve the desired pH levels."

Some Preventive steps

Regular checking

Certain parameters have to be checked in routine to maintain the freshness of pool water. These parameters are:

  • pH level
  • Chlorine level
  • Alkalinity
  • Cyanuric acid levels[/su_list]


Algaecide is one such chemical that will prevent the initial growth of algae in your pool. It can be added to the pool weekly, as a preventive measure for pool hygiene.

Removal of phosphates

Phosphate is one of the nutrients on which algae feed. To stop the breeding of algae in pool, phosphate should be removed and to do so, phosphate removal kits are available from swimming-pool chemical store.

Final Words

You will never appreciate  the complete draining of the pool to get rid of algae. So if you want to keep the pool clean and avoid trouble of treating the pool, it is better to stop the algae growth by taking the action now, than to repent later.

Bryan Mallory

My name is Bryan Mallory and I have over 25 years of experience in swimming pool, spa maintenance and repairs. With my experience and knowledge I can return your pool back to its best and keep it in peak condition.