3 Types of Pool Algae and How to Treat Them

Learn about green, yellow, and black algae and how to properly treat each kind

 Algae in your pool is an unpleasant problem that commonly burdens swimming pool owners.   In this article, you’ll learn about the most common types of algae and how to treat them effectively. 

 General Rule:  The best way to keep algae at bay is to properly maintain the chemical balance of your pool and water.  Be sure you have a good pool water testing kit so that you can monitor your water regularly. If you do that, algae won’t be able to get started and you should be able avoid the problem of fighting it.  If you found this warning too late, then keep reading!

 1) Green Algae:  The most common type of algae, green algae is relatively easy to get rid of.  At first, you might notice your water beginning to look dull, or small patches of green goop congregating around the edge of your pool.  If you suspect you might be having an issue with pool algae, check your free chlorine levels.  If they are dropping quickly or have dropped quickly, that’s a good sign you’re fighting some algae.

There are two main methods for fighting green algae, both of which are covered below.  When fighting algae, no matter which method you choose, it’s important to work quickly and not let down.  If you stop before it’s completely eradicated and your free chlorine levels are low, it will quickly grow back.  Make sure you are well stocked on needed pool chemicals and pool supplies before starting either process.

Fighting Algae Method 1 – without algaecide:  If you’re against using algaecide in your pool, you’ll be fighting algae with good ol’ basic chemistry.  The goal is to raise the free chlorine levels high enough so that the algae dies and can no longer grow.  To do this, you need to know your cyanuric acid (often called stabilizer or conditioner) level.   The higher your cayanuric acid level, the more chlorine will need to be used.  If your level is too low, the sun’s rays will destroy the chlorine. 

 It’s best, if possible, to adjust your cyanuric acid levels to the optimum level of 30-80ppm.  After this has been completed, shock your pool heavily with (preferably) liquid chlorine or bleach.  While shocking, scrub your pool all over to break any algae loose from your walls.  Run you’re your filter and clean as needed during this process.  The algae are dead when they turn a gray color, but it may take a long time to completely filter out.  The key to this method is to make sure you have enough chlorine on hand to blast your pool and keep your level up.

 Fighting Algae Method 2 – with algaecide:  If you’re not against using an algaecide to treat your pool, then you can utilize a copper algaecide that will kill algae quickly.  To start the process with algaecide, you simply need to shock your pool with a high level of chlorine and circulate your water.  Next, you’ll add in your copper algaecide and generally run your filter for 24 hours.  After this time there should be large amounts of dead algae.  If there aren’t, run through the process again.  After the algae dies, you can utilize a flocculent to sink the algae to the bottom where you can vacuum it out of your pool.  Filtering your water should help catch the dead algae as well.  Make sure that you clean your filter before you use it to filter algae as it likely contains some level of live algae from the previous circulation.

 2) Yellow Algae (Mustard Algae):  Similar in look to pollen or yellow dust, yellow algae is another common type of pool algae that can ruin your fun.  Yellow algae tend to grow in dark areas of your pool or on your pool walls.  It can be a bit harder to get rid of than green algae, but is generally treated with the same process as described above.

  3) Black Algae:  With a nasty outer surface that blocks the algae underneath from chemical treated pool water, black algae is often very difficult to completely eradicate.  The treatment methods are generally the same as for green and yellow algae, but there are a variety of specialized algaecides that are produced to help fight black algae in various ways[s1] . 

With over 40 years of experience in the business, Doheny’s Water Warehouse has the trusted pool algaecide supplies you need to effectively control algae for good. Say “goodbye” to yellow, green, mustard and pink: with our reliable pool algaecide products, the only color your pool water will be is clear. 

 Not sure which pool algaecide you should purchase? Call 1- 866-364-3697 to get your questions answered.