A pool in the backyard is a summer essential until the crystal blue water turns a murky green color overnight.
Pool algae is one of the most common issues that most pool owners face, and it can be tricky to know how to tackle it if you’re new to owning a pool.
In this article, I will cover some key information on cleaning your pool, including how to get algae out of a pool.
So, let’s get started.
What is pool algae and why does it grow?
Algae is a living plant organism that can appear in your pool very quickly. Algae often grows and spreads due to an imbalance of chlorine in the water in your pool.
There are a three common forms you can come across in your pool:
Green algae - Green algae is the most common form of pool algae as it grows due to a lack of sanitization (not enough chlorine) and filtration. It can also grow if the water has a high pH.
The good news is that this type of algae is easy to get rid of.
Yellow or mustard algae - Yellow algae is the second most common type of algae you’re likely to see in your pool in the areas that receive less sunlight.
Yellow algae is generally a challenge to get rid of and won’t be killed by any normal dose of a sanitizer such as chlorine or algaecide. As a result, you will need to kill it by super shocking your swimming pool.
Black algae - Black algae appears as little dark spots on your pool wall, and is the hardest algae to get rid of. That’s right - it’s even harder to kill than yellow algae!
To kill black algae, you will need to shock your pool alongside invest in some proper tools such as a tough pool brush.
How to get algae out of a pool
When you are assessing how to treat your pool for algae, you can tell the severity of the problem by simply observing how dark the water has become.
Light green pool water
One shock treatment should be enough to clear it if your pool is a light green. Algae feeds off high pH levels and chlorine isn't as effective in your pool when your pH is too high.
As a result, you will need to lower your pH using hydrochloric acid. Start off with around 1 to 2 liters of hydrochloric acid, making sure that you take extra care with it as it is highly toxic.
Following this, you will also need to shock your pool with 1 to 2 cups of chlorine.
Dark green pool water
If your pool water is a dark green color, then you’re going to need a higher dose of both acid and chlorine to kill the algae. 2 to 3 liters of acid over a longer duration of time and 2 to 3 cups (600g) of granulated chlorine.
If you have a vinyl lined pool, you should be sure to space out this treatment as it can be sensitive to harsh chemicals. I recommend doing this over 2 or 3 days to ensure that you’re protecting your pool’s vinyl.
Black green pool water
If you have black green pool water, then you will need to up the dosage of acid to 3 to 4 liters, and 3 to 4 cups of chlorine.
You will also need to be prepared to clean out your pool, as at this stage, it more than likely has debris all over the bottom of the pool that needs to be cleaned out before you dose and shock the pool.
If this process fails, then it is time to look into getting professional help to revive your pool back to health.
While this can be quite expensive, it might be that your pool needs to be drained and properly treated by professionals with the right equipment and expertise.
Notes on treating your pool for algae
If you notice that your pool is still cloudy after you have treated it, give it time. Once you’ve run the pump and filter for a full 24 hours, you should notice the water slowly returning to normal.
You need to regularly clean your pool. However, you will also need to check your pool filter often to make sure it is not full of dirt and debris that may cause improper flow.
Make sure that you are regularly skimming the surface of the pool to prevent dead leaves and debris from going into the filter. I recommend cleaning the pool every other day to stay on top of this.
How do I prevent algae from re-growing in my pool?
This is the age old question for pool owners! The best way to protect your pool from algae is to take preventative measures.
You will need to make sure that you are maintaining your pool on a regular basis, ensuring that the chlorine levels are right and that you are regularly cleaning it.
You will also need to shock your pool with a high dose of chlorine to kill any dormant bacteria or algae on a weekly basis.
While this may feel like a time consuming process, it’s much easier to prevent algae from growing than it is to kill it once it has infested your pool’s water.
That being said, it’s absolutely crucial that if you have a pool and you want to keep the water crystal blue, you will need to make sure that you are regularly maintaining it.
To kill the algae in your pool, you will need to lower the pH levels with hydrochloric acid and give it a shock treatment.
To determine how big of a dose you need to give your pool, you will need to assess the color of your pool and go from there.
If all else fails, you will need to contact professional help to help you revive your pool back to health.