Tips to Getting Rid of Algae in Your Swimming Pool

Algae, just saying the word to a swimming pool owner can bring a frown to their face and s even an audible groan.  Many pool owners find algae to be very frustrating, the bane of their pool’s existence.  Eliminating algae may take a bit of work on your part, but it’s not overwhelming if you follow a few simple steps.

While we are a home renovation contractor in Toronto, we are often called to do pool area construction projects.  I am also a pool owner who has struggled with keeping my pool crystal clear in the past.

#1 Identify It

It’s important to know what kind of algae you’re dealing with before you can begin to address it.  There are several types of algae that can grow in your pool.  Identifying the specific algae you are dealing with will help you eliminate the problem.

  1. The most common type of algae found in swimming pools is Green Algae.  You will find it floating on the surface or growing on the walls. Your pool water will not be clear and will have a green tinge.  Green algae is very slimy and can actually grow in sheets.
  2. Yellow algae (also called mustard algae).  It typically grows in the shady parts of your pool. If you have a tree hanging over part of your pool or an area that is shaded most of the day, likely you may find yellow algae.  Mustard algae is one of the more difficult types of algae to deal with and can often come back.  It is important to deal with this type of algae as soon as possible.
  3. Black algae can actually blue, black or dark green in different spots.  It is by far, the most difficult kind to get rid of once it’s in your pool.  It looks like a tar deposit and tends to be tiny spots.  Once your pool has black algae, it is very difficult to permanently get rid of as it tends to work its roots into the plaster or grout.  It will come back if not dealt with properly.
  4. Pink algae is actually more of a fungus. You can find it most often in the cracks, crevices and corners of the pool.  It will usually appear in just one area and look like pink spots.

There are several kinds of algae treatments for you pool you can buy to treat any of the above.

#2 Circulation 

Running your pump constantly is important to keeping the water circulating.  You’ll also need to check your filter and backwash often.  Many pool owners make the mistake of setting their pump and filter to run on a timer while on vacation to reduce expenses. Depending on weather and conditions in you pool this could be a mistake that results in algae.

#3 Brushing

Using a pool brush, brush down the pool walls to get as much algae off as possible, this will help when you add chemicals.  For a concrete pool, use a metal brush.  For a vinyl pool, it is best to use a nylon brush as the metal can actually tear the liner of this type of pool.

#4  Water Chemistry

Purchase a good quality test kit and test your PH levels on a regular basis.  Your ph levels should be in the range of 7.2 – 7.6, the alkalinity between 80 – 120 ppm, and your calcium hardness between 200 -400 ppm.  These levels will ensure that your chemicals will work properly when added to the swimming pool.

#5 Shock It

Add a chlorine based shocker as needed.  A good rule of thumb is one pound of shocker for every 10,000 gallons of pool water when there is no algae problem.  When algae is present, you should double the amount of shocker, so 2 pounds for every 10,000 gallons.

#6  Filter It

Once the shocker is added, allow the filter system to do its job.  After 24 hours your pool should have changed for the better.  If there is no improvement, add a second dose of the shocker at the regular “dose” of 1 pound per 10,000 gallons and repeat the cycle.

#7 Vacuum It

If you use your pool filter to vacuum, make sure you have it set to the waste setting.  This way means the waste will bypass the filter and be taken directly out of the pool.  Using this method helps to get the most algae out of your system so it doesn’t grow back again.

#8 Invest in Algaecide

Use a good algaecide to maintain the health of your pool and prevent growth of algae in the future.  Copper based algaecides are best for mustard algae and green algae.  Copper based product can cause staining of your pool if not used properly so it’s important to follow label directions closely.  Quat and polyquat algaecides are also available to be used if you’ve had problems with staining.  The polyquat algaecides tend to be a little more expensive.

Once you take care of the algae, continuing to maintain your pool can prevent the algae from returning.  Investing a little time and money can prevent you from spending more time and more money later.